Index: head/sys/dev/netmap/netmap_generic.c =================================================================== --- head/sys/dev/netmap/netmap_generic.c (revision 297297) +++ head/sys/dev/netmap/netmap_generic.c (revision 297298) @@ -1,865 +1,866 @@ /* * Copyright (C) 2013-2014 Universita` di Pisa. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ /* * This module implements netmap support on top of standard, * unmodified device drivers. * * A NIOCREGIF request is handled here if the device does not * have native support. TX and RX rings are emulated as follows: * * NIOCREGIF * We preallocate a block of TX mbufs (roughly as many as * tx descriptors; the number is not critical) to speed up * operation during transmissions. The refcount on most of * these buffers is artificially bumped up so we can recycle * them more easily. Also, the destructor is intercepted * so we use it as an interrupt notification to wake up * processes blocked on a poll(). * * For each receive ring we allocate one "struct mbq" * (an mbuf tailq plus a spinlock). We intercept packets * (through if_input) * on the receive path and put them in the mbq from which * netmap receive routines can grab them. * * TX: * in the generic_txsync() routine, netmap buffers are copied * (or linked, in a future) to the preallocated mbufs * and pushed to the transmit queue. Some of these mbufs * (those with NS_REPORT, or otherwise every half ring) * have the refcount=1, others have refcount=2. * When the destructor is invoked, we take that as * a notification that all mbufs up to that one in * the specific ring have been completed, and generate * the equivalent of a transmit interrupt. * * RX: * */ #ifdef __FreeBSD__ #include /* prerequisite */ __FBSDID("$FreeBSD$"); #include #include #include #include /* PROT_EXEC */ #include #include /* sockaddrs */ #include #include #include #include /* bus_dmamap_* in netmap_kern.h */ // XXX temporary - D() defined here #include #include #include #define rtnl_lock() ND("rtnl_lock called") #define rtnl_unlock() ND("rtnl_unlock called") #define MBUF_TXQ(m) ((m)->m_pkthdr.flowid) #define MBUF_RXQ(m) ((m)->m_pkthdr.flowid) #define smp_mb() /* * FreeBSD mbuf allocator/deallocator in emulation mode: * * We allocate EXT_PACKET mbuf+clusters, but need to set M_NOFREE * so that the destructor, if invoked, will not free the packet. * In principle we should set the destructor only on demand, * but since there might be a race we better do it on allocation. * As a consequence, we also need to set the destructor or we * would leak buffers. */ /* * mbuf wrappers */ /* mbuf destructor, also need to change the type to EXT_EXTREF, * add an M_NOFREE flag, and then clear the flag and * chain into uma_zfree(zone_pack, mf) * (or reinstall the buffer ?) */ #define SET_MBUF_DESTRUCTOR(m, fn) do { \ (m)->m_ext.ext_free = (void *)fn; \ (m)->m_ext.ext_type = EXT_EXTREF; \ } while (0) static void netmap_default_mbuf_destructor(struct mbuf *m) { /* restore original mbuf */ m->m_ext.ext_buf = m->m_data = m->m_ext.ext_arg1; m->m_ext.ext_arg1 = NULL; m->m_ext.ext_type = EXT_PACKET; m->m_ext.ext_free = NULL; if (GET_MBUF_REFCNT(m) == 0) SET_MBUF_REFCNT(m, 1); uma_zfree(zone_pack, m); } static inline struct mbuf * netmap_get_mbuf(int len) { struct mbuf *m; - m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR | M_NOFREE); + m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); if (m) { + m->m_flags |= M_NOFREE; /* XXXNP: Almost certainly incorrect. */ m->m_ext.ext_arg1 = m->m_ext.ext_buf; // XXX save m->m_ext.ext_free = (void *)netmap_default_mbuf_destructor; m->m_ext.ext_type = EXT_EXTREF; ND(5, "create m %p refcnt %d", m, GET_MBUF_REFCNT(m)); } return m; } #else /* linux */ #include "bsd_glue.h" #include /* rtnl_[un]lock() */ #include /* struct ethtool_ops, get_ringparam */ #include //#define REG_RESET #endif /* linux */ /* Common headers. */ #include #include #include /* ======================== usage stats =========================== */ #ifdef RATE_GENERIC #define IFRATE(x) x struct rate_stats { unsigned long txpkt; unsigned long txsync; unsigned long txirq; unsigned long rxpkt; unsigned long rxirq; unsigned long rxsync; }; struct rate_context { unsigned refcount; struct timer_list timer; struct rate_stats new; struct rate_stats old; }; #define RATE_PRINTK(_NAME_) \ printk( #_NAME_ " = %lu Hz\n", (cur._NAME_ - ctx->old._NAME_)/RATE_PERIOD); #define RATE_PERIOD 2 static void rate_callback(unsigned long arg) { struct rate_context * ctx = (struct rate_context *)arg; struct rate_stats cur = ctx->new; int r; RATE_PRINTK(txpkt); RATE_PRINTK(txsync); RATE_PRINTK(txirq); RATE_PRINTK(rxpkt); RATE_PRINTK(rxsync); RATE_PRINTK(rxirq); printk("\n"); ctx->old = cur; r = mod_timer(&ctx->timer, jiffies + msecs_to_jiffies(RATE_PERIOD * 1000)); if (unlikely(r)) D("[v1000] Error: mod_timer()"); } static struct rate_context rate_ctx; void generic_rate(int txp, int txs, int txi, int rxp, int rxs, int rxi) { if (txp) rate_ctx.new.txpkt++; if (txs) rate_ctx.new.txsync++; if (txi) rate_ctx.new.txirq++; if (rxp) rate_ctx.new.rxpkt++; if (rxs) rate_ctx.new.rxsync++; if (rxi) rate_ctx.new.rxirq++; } #else /* !RATE */ #define IFRATE(x) #endif /* !RATE */ /* =============== GENERIC NETMAP ADAPTER SUPPORT ================= */ /* * Wrapper used by the generic adapter layer to notify * the poller threads. Differently from netmap_rx_irq(), we check * only NAF_NETMAP_ON instead of NAF_NATIVE_ON to enable the irq. */ static void netmap_generic_irq(struct ifnet *ifp, u_int q, u_int *work_done) { struct netmap_adapter *na = NA(ifp); if (unlikely(!nm_netmap_on(na))) return; netmap_common_irq(ifp, q, work_done); } /* Enable/disable netmap mode for a generic network interface. */ static int generic_netmap_register(struct netmap_adapter *na, int enable) { struct netmap_generic_adapter *gna = (struct netmap_generic_adapter *)na; struct mbuf *m; int error; int i, r; if (!na) return EINVAL; #ifdef REG_RESET error = ifp->netdev_ops->ndo_stop(ifp); if (error) { return error; } #endif /* REG_RESET */ if (enable) { /* Enable netmap mode. */ /* Init the mitigation support on all the rx queues. */ gna->mit = malloc(na->num_rx_rings * sizeof(struct nm_generic_mit), M_DEVBUF, M_NOWAIT | M_ZERO); if (!gna->mit) { D("mitigation allocation failed"); error = ENOMEM; goto out; } for (r=0; rnum_rx_rings; r++) netmap_mitigation_init(&gna->mit[r], r, na); /* Initialize the rx queue, as generic_rx_handler() can * be called as soon as netmap_catch_rx() returns. */ for (r=0; rnum_rx_rings; r++) { mbq_safe_init(&na->rx_rings[r].rx_queue); } /* * Preallocate packet buffers for the tx rings. */ for (r=0; rnum_tx_rings; r++) na->tx_rings[r].tx_pool = NULL; for (r=0; rnum_tx_rings; r++) { na->tx_rings[r].tx_pool = malloc(na->num_tx_desc * sizeof(struct mbuf *), M_DEVBUF, M_NOWAIT | M_ZERO); if (!na->tx_rings[r].tx_pool) { D("tx_pool allocation failed"); error = ENOMEM; goto free_tx_pools; } for (i=0; inum_tx_desc; i++) na->tx_rings[r].tx_pool[i] = NULL; for (i=0; inum_tx_desc; i++) { m = netmap_get_mbuf(NETMAP_BUF_SIZE(na)); if (!m) { D("tx_pool[%d] allocation failed", i); error = ENOMEM; goto free_tx_pools; } na->tx_rings[r].tx_pool[i] = m; } } rtnl_lock(); /* Prepare to intercept incoming traffic. */ error = netmap_catch_rx(gna, 1); if (error) { D("netdev_rx_handler_register() failed (%d)", error); goto register_handler; } na->na_flags |= NAF_NETMAP_ON; /* Make netmap control the packet steering. */ netmap_catch_tx(gna, 1); rtnl_unlock(); #ifdef RATE_GENERIC if (rate_ctx.refcount == 0) { D("setup_timer()"); memset(&rate_ctx, 0, sizeof(rate_ctx)); setup_timer(&rate_ctx.timer, &rate_callback, (unsigned long)&rate_ctx); if (mod_timer(&rate_ctx.timer, jiffies + msecs_to_jiffies(1500))) { D("Error: mod_timer()"); } } rate_ctx.refcount++; #endif /* RATE */ } else if (na->tx_rings[0].tx_pool) { /* Disable netmap mode. We enter here only if the previous generic_netmap_register(na, 1) was successfull. If it was not, na->tx_rings[0].tx_pool was set to NULL by the error handling code below. */ rtnl_lock(); na->na_flags &= ~NAF_NETMAP_ON; /* Release packet steering control. */ netmap_catch_tx(gna, 0); /* Do not intercept packets on the rx path. */ netmap_catch_rx(gna, 0); rtnl_unlock(); /* Free the mbufs going to the netmap rings */ for (r=0; rnum_rx_rings; r++) { mbq_safe_purge(&na->rx_rings[r].rx_queue); mbq_safe_destroy(&na->rx_rings[r].rx_queue); } for (r=0; rnum_rx_rings; r++) netmap_mitigation_cleanup(&gna->mit[r]); free(gna->mit, M_DEVBUF); for (r=0; rnum_tx_rings; r++) { for (i=0; inum_tx_desc; i++) { m_freem(na->tx_rings[r].tx_pool[i]); } free(na->tx_rings[r].tx_pool, M_DEVBUF); } #ifdef RATE_GENERIC if (--rate_ctx.refcount == 0) { D("del_timer()"); del_timer(&rate_ctx.timer); } #endif } #ifdef REG_RESET error = ifp->netdev_ops->ndo_open(ifp); if (error) { goto free_tx_pools; } #endif return 0; register_handler: rtnl_unlock(); free_tx_pools: for (r=0; rnum_tx_rings; r++) { if (na->tx_rings[r].tx_pool == NULL) continue; for (i=0; inum_tx_desc; i++) if (na->tx_rings[r].tx_pool[i]) m_freem(na->tx_rings[r].tx_pool[i]); free(na->tx_rings[r].tx_pool, M_DEVBUF); na->tx_rings[r].tx_pool = NULL; } for (r=0; rnum_rx_rings; r++) { netmap_mitigation_cleanup(&gna->mit[r]); mbq_safe_destroy(&na->rx_rings[r].rx_queue); } free(gna->mit, M_DEVBUF); out: return error; } /* * Callback invoked when the device driver frees an mbuf used * by netmap to transmit a packet. This usually happens when * the NIC notifies the driver that transmission is completed. */ static void generic_mbuf_destructor(struct mbuf *m) { netmap_generic_irq(MBUF_IFP(m), MBUF_TXQ(m), NULL); #ifdef __FreeBSD__ if (netmap_verbose) RD(5, "Tx irq (%p) queue %d index %d" , m, MBUF_TXQ(m), (int)(uintptr_t)m->m_ext.ext_arg1); netmap_default_mbuf_destructor(m); #endif /* __FreeBSD__ */ IFRATE(rate_ctx.new.txirq++); } extern int netmap_adaptive_io; /* Record completed transmissions and update hwtail. * * The oldest tx buffer not yet completed is at nr_hwtail + 1, * nr_hwcur is the first unsent buffer. */ static u_int generic_netmap_tx_clean(struct netmap_kring *kring) { u_int const lim = kring->nkr_num_slots - 1; u_int nm_i = nm_next(kring->nr_hwtail, lim); u_int hwcur = kring->nr_hwcur; u_int n = 0; struct mbuf **tx_pool = kring->tx_pool; while (nm_i != hwcur) { /* buffers not completed */ struct mbuf *m = tx_pool[nm_i]; if (unlikely(m == NULL)) { /* this is done, try to replenish the entry */ tx_pool[nm_i] = m = netmap_get_mbuf(NETMAP_BUF_SIZE(kring->na)); if (unlikely(m == NULL)) { D("mbuf allocation failed, XXX error"); // XXX how do we proceed ? break ? return -ENOMEM; } } else if (GET_MBUF_REFCNT(m) != 1) { break; /* This mbuf is still busy: its refcnt is 2. */ } n++; nm_i = nm_next(nm_i, lim); #if 0 /* rate adaptation */ if (netmap_adaptive_io > 1) { if (n >= netmap_adaptive_io) break; } else if (netmap_adaptive_io) { /* if hwcur - nm_i < lim/8 do an early break * so we prevent the sender from stalling. See CVT. */ if (hwcur >= nm_i) { if (hwcur - nm_i < lim/2) break; } else { if (hwcur + lim + 1 - nm_i < lim/2) break; } } #endif } kring->nr_hwtail = nm_prev(nm_i, lim); ND("tx completed [%d] -> hwtail %d", n, kring->nr_hwtail); return n; } /* * We have pending packets in the driver between nr_hwtail +1 and hwcur. * Compute a position in the middle, to be used to generate * a notification. */ static inline u_int generic_tx_event_middle(struct netmap_kring *kring, u_int hwcur) { u_int n = kring->nkr_num_slots; u_int ntc = nm_next(kring->nr_hwtail, n-1); u_int e; if (hwcur >= ntc) { e = (hwcur + ntc) / 2; } else { /* wrap around */ e = (hwcur + n + ntc) / 2; if (e >= n) { e -= n; } } if (unlikely(e >= n)) { D("This cannot happen"); e = 0; } return e; } /* * We have pending packets in the driver between nr_hwtail+1 and hwcur. * Schedule a notification approximately in the middle of the two. * There is a race but this is only called within txsync which does * a double check. */ static void generic_set_tx_event(struct netmap_kring *kring, u_int hwcur) { struct mbuf *m; u_int e; if (nm_next(kring->nr_hwtail, kring->nkr_num_slots -1) == hwcur) { return; /* all buffers are free */ } e = generic_tx_event_middle(kring, hwcur); m = kring->tx_pool[e]; ND(5, "Request Event at %d mbuf %p refcnt %d", e, m, m ? GET_MBUF_REFCNT(m) : -2 ); if (m == NULL) { /* This can happen if there is already an event on the netmap slot 'e': There is nothing to do. */ return; } kring->tx_pool[e] = NULL; SET_MBUF_DESTRUCTOR(m, generic_mbuf_destructor); // XXX wmb() ? /* Decrement the refcount an free it if we have the last one. */ m_freem(m); smp_mb(); } /* * generic_netmap_txsync() transforms netmap buffers into mbufs * and passes them to the standard device driver * (ndo_start_xmit() or ifp->if_transmit() ). * On linux this is not done directly, but using dev_queue_xmit(), * since it implements the TX flow control (and takes some locks). */ static int generic_netmap_txsync(struct netmap_kring *kring, int flags) { struct netmap_adapter *na = kring->na; struct ifnet *ifp = na->ifp; struct netmap_ring *ring = kring->ring; u_int nm_i; /* index into the netmap ring */ // j u_int const lim = kring->nkr_num_slots - 1; u_int const head = kring->rhead; u_int ring_nr = kring->ring_id; IFRATE(rate_ctx.new.txsync++); // TODO: handle the case of mbuf allocation failure rmb(); /* * First part: process new packets to send. */ nm_i = kring->nr_hwcur; if (nm_i != head) { /* we have new packets to send */ while (nm_i != head) { struct netmap_slot *slot = &ring->slot[nm_i]; u_int len = slot->len; void *addr = NMB(na, slot); /* device-specific */ struct mbuf *m; int tx_ret; NM_CHECK_ADDR_LEN(na, addr, len); /* Tale a mbuf from the tx pool and copy in the user packet. */ m = kring->tx_pool[nm_i]; if (unlikely(!m)) { RD(5, "This should never happen"); kring->tx_pool[nm_i] = m = netmap_get_mbuf(NETMAP_BUF_SIZE(na)); if (unlikely(m == NULL)) { D("mbuf allocation failed"); break; } } /* XXX we should ask notifications when NS_REPORT is set, * or roughly every half frame. We can optimize this * by lazily requesting notifications only when a * transmission fails. Probably the best way is to * break on failures and set notifications when * ring->cur == ring->tail || nm_i != cur */ tx_ret = generic_xmit_frame(ifp, m, addr, len, ring_nr); if (unlikely(tx_ret)) { ND(5, "start_xmit failed: err %d [nm_i %u, head %u, hwtail %u]", tx_ret, nm_i, head, kring->nr_hwtail); /* * No room for this mbuf in the device driver. * Request a notification FOR A PREVIOUS MBUF, * then call generic_netmap_tx_clean(kring) to do the * double check and see if we can free more buffers. * If there is space continue, else break; * NOTE: the double check is necessary if the problem * occurs in the txsync call after selrecord(). * Also, we need some way to tell the caller that not * all buffers were queued onto the device (this was * not a problem with native netmap driver where space * is preallocated). The bridge has a similar problem * and we solve it there by dropping the excess packets. */ generic_set_tx_event(kring, nm_i); if (generic_netmap_tx_clean(kring)) { /* space now available */ continue; } else { break; } } slot->flags &= ~(NS_REPORT | NS_BUF_CHANGED); nm_i = nm_next(nm_i, lim); IFRATE(rate_ctx.new.txpkt ++); } /* Update hwcur to the next slot to transmit. */ kring->nr_hwcur = nm_i; /* not head, we could break early */ } /* * Second, reclaim completed buffers */ if (flags & NAF_FORCE_RECLAIM || nm_kr_txempty(kring)) { /* No more available slots? Set a notification event * on a netmap slot that will be cleaned in the future. * No doublecheck is performed, since txsync() will be * called twice by netmap_poll(). */ generic_set_tx_event(kring, nm_i); } ND("tx #%d, hwtail = %d", n, kring->nr_hwtail); generic_netmap_tx_clean(kring); return 0; } /* * This handler is registered (through netmap_catch_rx()) * within the attached network interface * in the RX subsystem, so that every mbuf passed up by * the driver can be stolen to the network stack. * Stolen packets are put in a queue where the * generic_netmap_rxsync() callback can extract them. */ void generic_rx_handler(struct ifnet *ifp, struct mbuf *m) { struct netmap_adapter *na = NA(ifp); struct netmap_generic_adapter *gna = (struct netmap_generic_adapter *)na; u_int work_done; u_int rr = MBUF_RXQ(m); // receive ring number if (rr >= na->num_rx_rings) { rr = rr % na->num_rx_rings; // XXX expensive... } /* limit the size of the queue */ if (unlikely(mbq_len(&na->rx_rings[rr].rx_queue) > 1024)) { m_freem(m); } else { mbq_safe_enqueue(&na->rx_rings[rr].rx_queue, m); } if (netmap_generic_mit < 32768) { /* no rx mitigation, pass notification up */ netmap_generic_irq(na->ifp, rr, &work_done); IFRATE(rate_ctx.new.rxirq++); } else { /* same as send combining, filter notification if there is a * pending timer, otherwise pass it up and start a timer. */ if (likely(netmap_mitigation_active(&gna->mit[rr]))) { /* Record that there is some pending work. */ gna->mit[rr].mit_pending = 1; } else { netmap_generic_irq(na->ifp, rr, &work_done); IFRATE(rate_ctx.new.rxirq++); netmap_mitigation_start(&gna->mit[rr]); } } } /* * generic_netmap_rxsync() extracts mbufs from the queue filled by * generic_netmap_rx_handler() and puts their content in the netmap * receive ring. * Access must be protected because the rx handler is asynchronous, */ static int generic_netmap_rxsync(struct netmap_kring *kring, int flags) { struct netmap_ring *ring = kring->ring; struct netmap_adapter *na = kring->na; u_int nm_i; /* index into the netmap ring */ //j, u_int n; u_int const lim = kring->nkr_num_slots - 1; u_int const head = kring->rhead; int force_update = (flags & NAF_FORCE_READ) || kring->nr_kflags & NKR_PENDINTR; if (head > lim) return netmap_ring_reinit(kring); /* * First part: import newly received packets. */ if (netmap_no_pendintr || force_update) { /* extract buffers from the rx queue, stop at most one * slot before nr_hwcur (stop_i) */ uint16_t slot_flags = kring->nkr_slot_flags; u_int stop_i = nm_prev(kring->nr_hwcur, lim); nm_i = kring->nr_hwtail; /* first empty slot in the receive ring */ for (n = 0; nm_i != stop_i; n++) { int len; void *addr = NMB(na, &ring->slot[nm_i]); struct mbuf *m; /* we only check the address here on generic rx rings */ if (addr == NETMAP_BUF_BASE(na)) { /* Bad buffer */ return netmap_ring_reinit(kring); } /* * Call the locked version of the function. * XXX Ideally we could grab a batch of mbufs at once * and save some locking overhead. */ m = mbq_safe_dequeue(&kring->rx_queue); if (!m) /* no more data */ break; len = MBUF_LEN(m); m_copydata(m, 0, len, addr); ring->slot[nm_i].len = len; ring->slot[nm_i].flags = slot_flags; m_freem(m); nm_i = nm_next(nm_i, lim); } if (n) { kring->nr_hwtail = nm_i; IFRATE(rate_ctx.new.rxpkt += n); } kring->nr_kflags &= ~NKR_PENDINTR; } // XXX should we invert the order ? /* * Second part: skip past packets that userspace has released. */ nm_i = kring->nr_hwcur; if (nm_i != head) { /* Userspace has released some packets. */ for (n = 0; nm_i != head; n++) { struct netmap_slot *slot = &ring->slot[nm_i]; slot->flags &= ~NS_BUF_CHANGED; nm_i = nm_next(nm_i, lim); } kring->nr_hwcur = head; } IFRATE(rate_ctx.new.rxsync++); return 0; } static void generic_netmap_dtor(struct netmap_adapter *na) { struct netmap_generic_adapter *gna = (struct netmap_generic_adapter*)na; struct ifnet *ifp = netmap_generic_getifp(gna); struct netmap_adapter *prev_na = gna->prev; if (prev_na != NULL) { D("Released generic NA %p", gna); if_rele(ifp); netmap_adapter_put(prev_na); if (na->ifp == NULL) { /* * The driver has been removed without releasing * the reference so we need to do it here. */ netmap_adapter_put(prev_na); } } WNA(ifp) = prev_na; D("Restored native NA %p", prev_na); na->ifp = NULL; } /* * generic_netmap_attach() makes it possible to use netmap on * a device without native netmap support. * This is less performant than native support but potentially * faster than raw sockets or similar schemes. * * In this "emulated" mode, netmap rings do not necessarily * have the same size as those in the NIC. We use a default * value and possibly override it if the OS has ways to fetch the * actual configuration. */ int generic_netmap_attach(struct ifnet *ifp) { struct netmap_adapter *na; struct netmap_generic_adapter *gna; int retval; u_int num_tx_desc, num_rx_desc; num_tx_desc = num_rx_desc = netmap_generic_ringsize; /* starting point */ generic_find_num_desc(ifp, &num_tx_desc, &num_rx_desc); /* ignore errors */ ND("Netmap ring size: TX = %d, RX = %d", num_tx_desc, num_rx_desc); if (num_tx_desc == 0 || num_rx_desc == 0) { D("Device has no hw slots (tx %u, rx %u)", num_tx_desc, num_rx_desc); return EINVAL; } gna = malloc(sizeof(*gna), M_DEVBUF, M_NOWAIT | M_ZERO); if (gna == NULL) { D("no memory on attach, give up"); return ENOMEM; } na = (struct netmap_adapter *)gna; strncpy(na->name, ifp->if_xname, sizeof(na->name)); na->ifp = ifp; na->num_tx_desc = num_tx_desc; na->num_rx_desc = num_rx_desc; na->nm_register = &generic_netmap_register; na->nm_txsync = &generic_netmap_txsync; na->nm_rxsync = &generic_netmap_rxsync; na->nm_dtor = &generic_netmap_dtor; /* when using generic, NAF_NETMAP_ON is set so we force * NAF_SKIP_INTR to use the regular interrupt handler */ na->na_flags = NAF_SKIP_INTR | NAF_HOST_RINGS; ND("[GNA] num_tx_queues(%d), real_num_tx_queues(%d), len(%lu)", ifp->num_tx_queues, ifp->real_num_tx_queues, ifp->tx_queue_len); ND("[GNA] num_rx_queues(%d), real_num_rx_queues(%d)", ifp->num_rx_queues, ifp->real_num_rx_queues); generic_find_num_queues(ifp, &na->num_tx_rings, &na->num_rx_rings); retval = netmap_attach_common(na); if (retval) { free(gna, M_DEVBUF); } return retval; } Index: head/sys/kern/kern_mbuf.c =================================================================== --- head/sys/kern/kern_mbuf.c (revision 297297) +++ head/sys/kern/kern_mbuf.c (revision 297298) @@ -1,946 +1,948 @@ /*- * Copyright (c) 2004, 2005, * Bosko Milekic . All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice unmodified, this list of conditions and the following * disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include __FBSDID("$FreeBSD$"); #include "opt_param.h" #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /* * In FreeBSD, Mbufs and Mbuf Clusters are allocated from UMA * Zones. * * Mbuf Clusters (2K, contiguous) are allocated from the Cluster * Zone. The Zone can be capped at kern.ipc.nmbclusters, if the * administrator so desires. * * Mbufs are allocated from a UMA Master Zone called the Mbuf * Zone. * * Additionally, FreeBSD provides a Packet Zone, which it * configures as a Secondary Zone to the Mbuf Master Zone, * thus sharing backend Slab kegs with the Mbuf Master Zone. * * Thus common-case allocations and locking are simplified: * * m_clget() m_getcl() * | | * | .------------>[(Packet Cache)] m_get(), m_gethdr() * | | [ Packet ] | * [(Cluster Cache)] [ Secondary ] [ (Mbuf Cache) ] * [ Cluster Zone ] [ Zone ] [ Mbuf Master Zone ] * | \________ | * [ Cluster Keg ] \ / * | [ Mbuf Keg ] * [ Cluster Slabs ] | * | [ Mbuf Slabs ] * \____________(VM)_________________/ * * * Whenever an object is allocated with uma_zalloc() out of * one of the Zones its _ctor_ function is executed. The same * for any deallocation through uma_zfree() the _dtor_ function * is executed. * * Caches are per-CPU and are filled from the Master Zone. * * Whenever an object is allocated from the underlying global * memory pool it gets pre-initialized with the _zinit_ functions. * When the Keg's are overfull objects get decomissioned with * _zfini_ functions and free'd back to the global memory pool. * */ int nmbufs; /* limits number of mbufs */ int nmbclusters; /* limits number of mbuf clusters */ int nmbjumbop; /* limits number of page size jumbo clusters */ int nmbjumbo9; /* limits number of 9k jumbo clusters */ int nmbjumbo16; /* limits number of 16k jumbo clusters */ static quad_t maxmbufmem; /* overall real memory limit for all mbufs */ SYSCTL_QUAD(_kern_ipc, OID_AUTO, maxmbufmem, CTLFLAG_RDTUN | CTLFLAG_NOFETCH, &maxmbufmem, 0, "Maximum real memory allocatable to various mbuf types"); /* * tunable_mbinit() has to be run before any mbuf allocations are done. */ static void tunable_mbinit(void *dummy) { quad_t realmem; /* * The default limit for all mbuf related memory is 1/2 of all * available kernel memory (physical or kmem). * At most it can be 3/4 of available kernel memory. */ realmem = qmin((quad_t)physmem * PAGE_SIZE, vm_kmem_size); maxmbufmem = realmem / 2; TUNABLE_QUAD_FETCH("kern.ipc.maxmbufmem", &maxmbufmem); if (maxmbufmem > realmem / 4 * 3) maxmbufmem = realmem / 4 * 3; TUNABLE_INT_FETCH("kern.ipc.nmbclusters", &nmbclusters); if (nmbclusters == 0) nmbclusters = maxmbufmem / MCLBYTES / 4; TUNABLE_INT_FETCH("kern.ipc.nmbjumbop", &nmbjumbop); if (nmbjumbop == 0) nmbjumbop = maxmbufmem / MJUMPAGESIZE / 4; TUNABLE_INT_FETCH("kern.ipc.nmbjumbo9", &nmbjumbo9); if (nmbjumbo9 == 0) nmbjumbo9 = maxmbufmem / MJUM9BYTES / 6; TUNABLE_INT_FETCH("kern.ipc.nmbjumbo16", &nmbjumbo16); if (nmbjumbo16 == 0) nmbjumbo16 = maxmbufmem / MJUM16BYTES / 6; /* * We need at least as many mbufs as we have clusters of * the various types added together. */ TUNABLE_INT_FETCH("kern.ipc.nmbufs", &nmbufs); if (nmbufs < nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) nmbufs = lmax(maxmbufmem / MSIZE / 5, nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16); } SYSINIT(tunable_mbinit, SI_SUB_KMEM, SI_ORDER_MIDDLE, tunable_mbinit, NULL); static int sysctl_nmbclusters(SYSCTL_HANDLER_ARGS) { int error, newnmbclusters; newnmbclusters = nmbclusters; error = sysctl_handle_int(oidp, &newnmbclusters, 0, req); if (error == 0 && req->newptr && newnmbclusters != nmbclusters) { if (newnmbclusters > nmbclusters && nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { nmbclusters = newnmbclusters; nmbclusters = uma_zone_set_max(zone_clust, nmbclusters); EVENTHANDLER_INVOKE(nmbclusters_change); } else error = EINVAL; } return (error); } SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbclusters, CTLTYPE_INT|CTLFLAG_RW, &nmbclusters, 0, sysctl_nmbclusters, "IU", "Maximum number of mbuf clusters allowed"); static int sysctl_nmbjumbop(SYSCTL_HANDLER_ARGS) { int error, newnmbjumbop; newnmbjumbop = nmbjumbop; error = sysctl_handle_int(oidp, &newnmbjumbop, 0, req); if (error == 0 && req->newptr && newnmbjumbop != nmbjumbop) { if (newnmbjumbop > nmbjumbop && nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { nmbjumbop = newnmbjumbop; nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop); } else error = EINVAL; } return (error); } SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbop, CTLTYPE_INT|CTLFLAG_RW, &nmbjumbop, 0, sysctl_nmbjumbop, "IU", "Maximum number of mbuf page size jumbo clusters allowed"); static int sysctl_nmbjumbo9(SYSCTL_HANDLER_ARGS) { int error, newnmbjumbo9; newnmbjumbo9 = nmbjumbo9; error = sysctl_handle_int(oidp, &newnmbjumbo9, 0, req); if (error == 0 && req->newptr && newnmbjumbo9 != nmbjumbo9) { if (newnmbjumbo9 > nmbjumbo9 && nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { nmbjumbo9 = newnmbjumbo9; nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9); } else error = EINVAL; } return (error); } SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo9, CTLTYPE_INT|CTLFLAG_RW, &nmbjumbo9, 0, sysctl_nmbjumbo9, "IU", "Maximum number of mbuf 9k jumbo clusters allowed"); static int sysctl_nmbjumbo16(SYSCTL_HANDLER_ARGS) { int error, newnmbjumbo16; newnmbjumbo16 = nmbjumbo16; error = sysctl_handle_int(oidp, &newnmbjumbo16, 0, req); if (error == 0 && req->newptr && newnmbjumbo16 != nmbjumbo16) { if (newnmbjumbo16 > nmbjumbo16 && nmbufs >= nmbclusters + nmbjumbop + nmbjumbo9 + nmbjumbo16) { nmbjumbo16 = newnmbjumbo16; nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16); } else error = EINVAL; } return (error); } SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbjumbo16, CTLTYPE_INT|CTLFLAG_RW, &nmbjumbo16, 0, sysctl_nmbjumbo16, "IU", "Maximum number of mbuf 16k jumbo clusters allowed"); static int sysctl_nmbufs(SYSCTL_HANDLER_ARGS) { int error, newnmbufs; newnmbufs = nmbufs; error = sysctl_handle_int(oidp, &newnmbufs, 0, req); if (error == 0 && req->newptr && newnmbufs != nmbufs) { if (newnmbufs > nmbufs) { nmbufs = newnmbufs; nmbufs = uma_zone_set_max(zone_mbuf, nmbufs); EVENTHANDLER_INVOKE(nmbufs_change); } else error = EINVAL; } return (error); } SYSCTL_PROC(_kern_ipc, OID_AUTO, nmbufs, CTLTYPE_INT|CTLFLAG_RW, &nmbufs, 0, sysctl_nmbufs, "IU", "Maximum number of mbufs allowed"); /* * Zones from which we allocate. */ uma_zone_t zone_mbuf; uma_zone_t zone_clust; uma_zone_t zone_pack; uma_zone_t zone_jumbop; uma_zone_t zone_jumbo9; uma_zone_t zone_jumbo16; /* * Local prototypes. */ static int mb_ctor_mbuf(void *, int, void *, int); static int mb_ctor_clust(void *, int, void *, int); static int mb_ctor_pack(void *, int, void *, int); static void mb_dtor_mbuf(void *, int, void *); static void mb_dtor_pack(void *, int, void *); static int mb_zinit_pack(void *, int, int); static void mb_zfini_pack(void *, int); static void mb_reclaim(uma_zone_t, int); static void *mbuf_jumbo_alloc(uma_zone_t, vm_size_t, uint8_t *, int); /* Ensure that MSIZE is a power of 2. */ CTASSERT((((MSIZE - 1) ^ MSIZE) + 1) >> 1 == MSIZE); /* * Initialize FreeBSD Network buffer allocation. */ static void mbuf_init(void *dummy) { /* * Configure UMA zones for Mbufs, Clusters, and Packets. */ zone_mbuf = uma_zcreate(MBUF_MEM_NAME, MSIZE, mb_ctor_mbuf, mb_dtor_mbuf, #ifdef INVARIANTS trash_init, trash_fini, #else NULL, NULL, #endif MSIZE - 1, UMA_ZONE_MAXBUCKET); if (nmbufs > 0) nmbufs = uma_zone_set_max(zone_mbuf, nmbufs); uma_zone_set_warning(zone_mbuf, "kern.ipc.nmbufs limit reached"); uma_zone_set_maxaction(zone_mbuf, mb_reclaim); zone_clust = uma_zcreate(MBUF_CLUSTER_MEM_NAME, MCLBYTES, mb_ctor_clust, #ifdef INVARIANTS trash_dtor, trash_init, trash_fini, #else NULL, NULL, NULL, #endif UMA_ALIGN_PTR, 0); if (nmbclusters > 0) nmbclusters = uma_zone_set_max(zone_clust, nmbclusters); uma_zone_set_warning(zone_clust, "kern.ipc.nmbclusters limit reached"); uma_zone_set_maxaction(zone_clust, mb_reclaim); zone_pack = uma_zsecond_create(MBUF_PACKET_MEM_NAME, mb_ctor_pack, mb_dtor_pack, mb_zinit_pack, mb_zfini_pack, zone_mbuf); /* Make jumbo frame zone too. Page size, 9k and 16k. */ zone_jumbop = uma_zcreate(MBUF_JUMBOP_MEM_NAME, MJUMPAGESIZE, mb_ctor_clust, #ifdef INVARIANTS trash_dtor, trash_init, trash_fini, #else NULL, NULL, NULL, #endif UMA_ALIGN_PTR, 0); if (nmbjumbop > 0) nmbjumbop = uma_zone_set_max(zone_jumbop, nmbjumbop); uma_zone_set_warning(zone_jumbop, "kern.ipc.nmbjumbop limit reached"); uma_zone_set_maxaction(zone_jumbop, mb_reclaim); zone_jumbo9 = uma_zcreate(MBUF_JUMBO9_MEM_NAME, MJUM9BYTES, mb_ctor_clust, #ifdef INVARIANTS trash_dtor, trash_init, trash_fini, #else NULL, NULL, NULL, #endif UMA_ALIGN_PTR, 0); uma_zone_set_allocf(zone_jumbo9, mbuf_jumbo_alloc); if (nmbjumbo9 > 0) nmbjumbo9 = uma_zone_set_max(zone_jumbo9, nmbjumbo9); uma_zone_set_warning(zone_jumbo9, "kern.ipc.nmbjumbo9 limit reached"); uma_zone_set_maxaction(zone_jumbo9, mb_reclaim); zone_jumbo16 = uma_zcreate(MBUF_JUMBO16_MEM_NAME, MJUM16BYTES, mb_ctor_clust, #ifdef INVARIANTS trash_dtor, trash_init, trash_fini, #else NULL, NULL, NULL, #endif UMA_ALIGN_PTR, 0); uma_zone_set_allocf(zone_jumbo16, mbuf_jumbo_alloc); if (nmbjumbo16 > 0) nmbjumbo16 = uma_zone_set_max(zone_jumbo16, nmbjumbo16); uma_zone_set_warning(zone_jumbo16, "kern.ipc.nmbjumbo16 limit reached"); uma_zone_set_maxaction(zone_jumbo16, mb_reclaim); /* * Hook event handler for low-memory situation, used to * drain protocols and push data back to the caches (UMA * later pushes it back to VM). */ EVENTHANDLER_REGISTER(vm_lowmem, mb_reclaim, NULL, EVENTHANDLER_PRI_FIRST); } SYSINIT(mbuf, SI_SUB_MBUF, SI_ORDER_FIRST, mbuf_init, NULL); /* * UMA backend page allocator for the jumbo frame zones. * * Allocates kernel virtual memory that is backed by contiguous physical * pages. */ static void * mbuf_jumbo_alloc(uma_zone_t zone, vm_size_t bytes, uint8_t *flags, int wait) { /* Inform UMA that this allocator uses kernel_map/object. */ *flags = UMA_SLAB_KERNEL; return ((void *)kmem_alloc_contig(kernel_arena, bytes, wait, (vm_paddr_t)0, ~(vm_paddr_t)0, 1, 0, VM_MEMATTR_DEFAULT)); } /* * Constructor for Mbuf master zone. * * The 'arg' pointer points to a mb_args structure which * contains call-specific information required to support the * mbuf allocation API. See mbuf.h. */ static int mb_ctor_mbuf(void *mem, int size, void *arg, int how) { struct mbuf *m; struct mb_args *args; int error; int flags; short type; #ifdef INVARIANTS trash_ctor(mem, size, arg, how); #endif args = (struct mb_args *)arg; type = args->type; /* * The mbuf is initialized later. The caller has the * responsibility to set up any MAC labels too. */ if (type == MT_NOINIT) return (0); m = (struct mbuf *)mem; flags = args->flags; + MPASS((flags & M_NOFREE) == 0); error = m_init(m, how, type, flags); return (error); } /* * The Mbuf master zone destructor. */ static void mb_dtor_mbuf(void *mem, int size, void *arg) { struct mbuf *m; unsigned long flags; m = (struct mbuf *)mem; flags = (unsigned long)arg; KASSERT((m->m_flags & M_NOFREE) == 0, ("%s: M_NOFREE set", __func__)); if ((m->m_flags & M_PKTHDR) && !SLIST_EMPTY(&m->m_pkthdr.tags)) m_tag_delete_chain(m, NULL); #ifdef INVARIANTS trash_dtor(mem, size, arg); #endif } /* * The Mbuf Packet zone destructor. */ static void mb_dtor_pack(void *mem, int size, void *arg) { struct mbuf *m; m = (struct mbuf *)mem; if ((m->m_flags & M_PKTHDR) != 0) m_tag_delete_chain(m, NULL); /* Make sure we've got a clean cluster back. */ KASSERT((m->m_flags & M_EXT) == M_EXT, ("%s: M_EXT not set", __func__)); KASSERT(m->m_ext.ext_buf != NULL, ("%s: ext_buf == NULL", __func__)); KASSERT(m->m_ext.ext_free == NULL, ("%s: ext_free != NULL", __func__)); KASSERT(m->m_ext.ext_arg1 == NULL, ("%s: ext_arg1 != NULL", __func__)); KASSERT(m->m_ext.ext_arg2 == NULL, ("%s: ext_arg2 != NULL", __func__)); KASSERT(m->m_ext.ext_size == MCLBYTES, ("%s: ext_size != MCLBYTES", __func__)); KASSERT(m->m_ext.ext_type == EXT_PACKET, ("%s: ext_type != EXT_PACKET", __func__)); #ifdef INVARIANTS trash_dtor(m->m_ext.ext_buf, MCLBYTES, arg); #endif /* * If there are processes blocked on zone_clust, waiting for pages * to be freed up, * cause them to be woken up by draining the * packet zone. We are exposed to a race here * (in the check for * the UMA_ZFLAG_FULL) where we might miss the flag set, but that * is deliberate. We don't want to acquire the zone lock for every * mbuf free. */ if (uma_zone_exhausted_nolock(zone_clust)) zone_drain(zone_pack); } /* * The Cluster and Jumbo[PAGESIZE|9|16] zone constructor. * * Here the 'arg' pointer points to the Mbuf which we * are configuring cluster storage for. If 'arg' is * empty we allocate just the cluster without setting * the mbuf to it. See mbuf.h. */ static int mb_ctor_clust(void *mem, int size, void *arg, int how) { struct mbuf *m; #ifdef INVARIANTS trash_ctor(mem, size, arg, how); #endif m = (struct mbuf *)arg; if (m != NULL) { m->m_ext.ext_buf = (caddr_t)mem; m->m_data = m->m_ext.ext_buf; m->m_flags |= M_EXT; m->m_ext.ext_free = NULL; m->m_ext.ext_arg1 = NULL; m->m_ext.ext_arg2 = NULL; m->m_ext.ext_size = size; m->m_ext.ext_type = m_gettype(size); m->m_ext.ext_flags = EXT_FLAG_EMBREF; m->m_ext.ext_count = 1; } return (0); } /* * The Packet secondary zone's init routine, executed on the * object's transition from mbuf keg slab to zone cache. */ static int mb_zinit_pack(void *mem, int size, int how) { struct mbuf *m; m = (struct mbuf *)mem; /* m is virgin. */ if (uma_zalloc_arg(zone_clust, m, how) == NULL || m->m_ext.ext_buf == NULL) return (ENOMEM); m->m_ext.ext_type = EXT_PACKET; /* Override. */ #ifdef INVARIANTS trash_init(m->m_ext.ext_buf, MCLBYTES, how); #endif return (0); } /* * The Packet secondary zone's fini routine, executed on the * object's transition from zone cache to keg slab. */ static void mb_zfini_pack(void *mem, int size) { struct mbuf *m; m = (struct mbuf *)mem; #ifdef INVARIANTS trash_fini(m->m_ext.ext_buf, MCLBYTES); #endif uma_zfree_arg(zone_clust, m->m_ext.ext_buf, NULL); #ifdef INVARIANTS trash_dtor(mem, size, NULL); #endif } /* * The "packet" keg constructor. */ static int mb_ctor_pack(void *mem, int size, void *arg, int how) { struct mbuf *m; struct mb_args *args; int error, flags; short type; m = (struct mbuf *)mem; args = (struct mb_args *)arg; flags = args->flags; type = args->type; + MPASS((flags & M_NOFREE) == 0); #ifdef INVARIANTS trash_ctor(m->m_ext.ext_buf, MCLBYTES, arg, how); #endif error = m_init(m, how, type, flags); /* m_ext is already initialized. */ m->m_data = m->m_ext.ext_buf; m->m_flags = (flags | M_EXT); return (error); } /* * This is the protocol drain routine. Called by UMA whenever any of the * mbuf zones is closed to its limit. * * No locks should be held when this is called. The drain routines have to * presently acquire some locks which raises the possibility of lock order * reversal. */ static void mb_reclaim(uma_zone_t zone __unused, int pending __unused) { struct domain *dp; struct protosw *pr; WITNESS_WARN(WARN_GIANTOK | WARN_SLEEPOK | WARN_PANIC, NULL, __func__); for (dp = domains; dp != NULL; dp = dp->dom_next) for (pr = dp->dom_protosw; pr < dp->dom_protoswNPROTOSW; pr++) if (pr->pr_drain != NULL) (*pr->pr_drain)(); } /* * Clean up after mbufs with M_EXT storage attached to them if the * reference count hits 1. */ void mb_free_ext(struct mbuf *m) { volatile u_int *refcnt; struct mbuf *mref; int freembuf; KASSERT(m->m_flags & M_EXT, ("%s: M_EXT not set on %p", __func__, m)); /* See if this is the mbuf that holds the embedded refcount. */ if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { refcnt = &m->m_ext.ext_count; mref = m; } else { KASSERT(m->m_ext.ext_cnt != NULL, ("%s: no refcounting pointer on %p", __func__, m)); refcnt = m->m_ext.ext_cnt; mref = __containerof(refcnt, struct mbuf, m_ext.ext_count); } /* * Check if the header is embedded in the cluster. It is * important that we can't touch any of the mbuf fields * after we have freed the external storage, since mbuf * could have been embedded in it. */ freembuf = (m->m_flags & M_NOFREE) ? 0 : 1; /* Free attached storage if this mbuf is the only reference to it. */ if (*refcnt == 1 || atomic_fetchadd_int(refcnt, -1) == 1) { switch (m->m_ext.ext_type) { case EXT_PACKET: /* The packet zone is special. */ if (*refcnt == 0) *refcnt = 1; uma_zfree(zone_pack, mref); break; case EXT_CLUSTER: uma_zfree(zone_clust, m->m_ext.ext_buf); uma_zfree(zone_mbuf, mref); break; case EXT_JUMBOP: uma_zfree(zone_jumbop, m->m_ext.ext_buf); uma_zfree(zone_mbuf, mref); break; case EXT_JUMBO9: uma_zfree(zone_jumbo9, m->m_ext.ext_buf); uma_zfree(zone_mbuf, mref); break; case EXT_JUMBO16: uma_zfree(zone_jumbo16, m->m_ext.ext_buf); uma_zfree(zone_mbuf, mref); break; case EXT_SFBUF: sf_ext_free(m->m_ext.ext_arg1, m->m_ext.ext_arg2); uma_zfree(zone_mbuf, mref); break; case EXT_SFBUF_NOCACHE: sf_ext_free_nocache(m->m_ext.ext_arg1, m->m_ext.ext_arg2); uma_zfree(zone_mbuf, mref); break; case EXT_NET_DRV: case EXT_MOD_TYPE: case EXT_DISPOSABLE: KASSERT(m->m_ext.ext_free != NULL, ("%s: ext_free not set", __func__)); (*(m->m_ext.ext_free))(m, m->m_ext.ext_arg1, m->m_ext.ext_arg2); uma_zfree(zone_mbuf, mref); break; case EXT_EXTREF: KASSERT(m->m_ext.ext_free != NULL, ("%s: ext_free not set", __func__)); (*(m->m_ext.ext_free))(m, m->m_ext.ext_arg1, m->m_ext.ext_arg2); break; default: KASSERT(m->m_ext.ext_type == 0, ("%s: unknown ext_type", __func__)); } } if (freembuf && m != mref) uma_zfree(zone_mbuf, m); } /* * Official mbuf(9) allocation KPI for stack and drivers: * * m_get() - a single mbuf without any attachments, sys/mbuf.h. * m_gethdr() - a single mbuf initialized as M_PKTHDR, sys/mbuf.h. * m_getcl() - an mbuf + 2k cluster, sys/mbuf.h. * m_clget() - attach cluster to already allocated mbuf. * m_cljget() - attach jumbo cluster to already allocated mbuf. * m_get2() - allocate minimum mbuf that would fit size argument. * m_getm2() - allocate a chain of mbufs/clusters. * m_extadd() - attach external cluster to mbuf. * * m_free() - free single mbuf with its tags and ext, sys/mbuf.h. * m_freem() - free chain of mbufs. */ int m_clget(struct mbuf *m, int how) { KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT", __func__, m)); m->m_ext.ext_buf = (char *)NULL; uma_zalloc_arg(zone_clust, m, how); /* * On a cluster allocation failure, drain the packet zone and retry, * we might be able to loosen a few clusters up on the drain. */ if ((how & M_NOWAIT) && (m->m_ext.ext_buf == NULL)) { zone_drain(zone_pack); uma_zalloc_arg(zone_clust, m, how); } MBUF_PROBE2(m__clget, m, how); return (m->m_flags & M_EXT); } /* * m_cljget() is different from m_clget() as it can allocate clusters without * attaching them to an mbuf. In that case the return value is the pointer * to the cluster of the requested size. If an mbuf was specified, it gets * the cluster attached to it and the return value can be safely ignored. * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. */ void * m_cljget(struct mbuf *m, int how, int size) { uma_zone_t zone; void *retval; if (m != NULL) { KASSERT((m->m_flags & M_EXT) == 0, ("%s: mbuf %p has M_EXT", __func__, m)); m->m_ext.ext_buf = NULL; } zone = m_getzone(size); retval = uma_zalloc_arg(zone, m, how); MBUF_PROBE4(m__cljget, m, how, size, retval); return (retval); } /* * m_get2() allocates minimum mbuf that would fit "size" argument. */ struct mbuf * m_get2(int size, int how, short type, int flags) { struct mb_args args; struct mbuf *m, *n; args.flags = flags; args.type = type; if (size <= MHLEN || (size <= MLEN && (flags & M_PKTHDR) == 0)) return (uma_zalloc_arg(zone_mbuf, &args, how)); if (size <= MCLBYTES) return (uma_zalloc_arg(zone_pack, &args, how)); if (size > MJUMPAGESIZE) return (NULL); m = uma_zalloc_arg(zone_mbuf, &args, how); if (m == NULL) return (NULL); n = uma_zalloc_arg(zone_jumbop, m, how); if (n == NULL) { uma_zfree(zone_mbuf, m); return (NULL); } return (m); } /* * m_getjcl() returns an mbuf with a cluster of the specified size attached. * For size it takes MCLBYTES, MJUMPAGESIZE, MJUM9BYTES, MJUM16BYTES. */ struct mbuf * m_getjcl(int how, short type, int flags, int size) { struct mb_args args; struct mbuf *m, *n; uma_zone_t zone; if (size == MCLBYTES) return m_getcl(how, type, flags); args.flags = flags; args.type = type; m = uma_zalloc_arg(zone_mbuf, &args, how); if (m == NULL) return (NULL); zone = m_getzone(size); n = uma_zalloc_arg(zone, m, how); if (n == NULL) { uma_zfree(zone_mbuf, m); return (NULL); } return (m); } /* * Allocate a given length worth of mbufs and/or clusters (whatever fits * best) and return a pointer to the top of the allocated chain. If an * existing mbuf chain is provided, then we will append the new chain * to the existing one but still return the top of the newly allocated * chain. */ struct mbuf * m_getm2(struct mbuf *m, int len, int how, short type, int flags) { struct mbuf *mb, *nm = NULL, *mtail = NULL; KASSERT(len >= 0, ("%s: len is < 0", __func__)); /* Validate flags. */ flags &= (M_PKTHDR | M_EOR); /* Packet header mbuf must be first in chain. */ if ((flags & M_PKTHDR) && m != NULL) flags &= ~M_PKTHDR; /* Loop and append maximum sized mbufs to the chain tail. */ while (len > 0) { if (len > MCLBYTES) mb = m_getjcl(how, type, (flags & M_PKTHDR), MJUMPAGESIZE); else if (len >= MINCLSIZE) mb = m_getcl(how, type, (flags & M_PKTHDR)); else if (flags & M_PKTHDR) mb = m_gethdr(how, type); else mb = m_get(how, type); /* Fail the whole operation if one mbuf can't be allocated. */ if (mb == NULL) { if (nm != NULL) m_freem(nm); return (NULL); } /* Book keeping. */ len -= M_SIZE(mb); if (mtail != NULL) mtail->m_next = mb; else nm = mb; mtail = mb; flags &= ~M_PKTHDR; /* Only valid on the first mbuf. */ } if (flags & M_EOR) mtail->m_flags |= M_EOR; /* Only valid on the last mbuf. */ /* If mbuf was supplied, append new chain to the end of it. */ if (m != NULL) { for (mtail = m; mtail->m_next != NULL; mtail = mtail->m_next) ; mtail->m_next = nm; mtail->m_flags &= ~M_EOR; } else m = nm; return (m); } /*- * Configure a provided mbuf to refer to the provided external storage * buffer and setup a reference count for said buffer. * * Arguments: * mb The existing mbuf to which to attach the provided buffer. * buf The address of the provided external storage buffer. * size The size of the provided buffer. * freef A pointer to a routine that is responsible for freeing the * provided external storage buffer. * args A pointer to an argument structure (of any type) to be passed * to the provided freef routine (may be NULL). * flags Any other flags to be passed to the provided mbuf. * type The type that the external storage buffer should be * labeled with. * * Returns: * Nothing. */ void m_extadd(struct mbuf *mb, caddr_t buf, u_int size, void (*freef)(struct mbuf *, void *, void *), void *arg1, void *arg2, int flags, int type) { KASSERT(type != EXT_CLUSTER, ("%s: EXT_CLUSTER not allowed", __func__)); mb->m_flags |= (M_EXT | flags); mb->m_ext.ext_buf = buf; mb->m_data = mb->m_ext.ext_buf; mb->m_ext.ext_size = size; mb->m_ext.ext_free = freef; mb->m_ext.ext_arg1 = arg1; mb->m_ext.ext_arg2 = arg2; mb->m_ext.ext_type = type; if (type != EXT_EXTREF) { mb->m_ext.ext_count = 1; mb->m_ext.ext_flags = EXT_FLAG_EMBREF; } else mb->m_ext.ext_flags = 0; } /* * Free an entire chain of mbufs and associated external buffers, if * applicable. */ void m_freem(struct mbuf *mb) { MBUF_PROBE1(m__freem, mb); while (mb != NULL) mb = m_free(mb); } Index: head/sys/kern/uipc_mbuf.c =================================================================== --- head/sys/kern/uipc_mbuf.c (revision 297297) +++ head/sys/kern/uipc_mbuf.c (revision 297298) @@ -1,1869 +1,1869 @@ /*- * Copyright (c) 1982, 1986, 1988, 1991, 1993 * The Regents of the University of California. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 4. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * @(#)uipc_mbuf.c 8.2 (Berkeley) 1/4/94 */ #include __FBSDID("$FreeBSD$"); #include "opt_param.h" #include "opt_mbuf_stress_test.h" #include "opt_mbuf_profiling.h" #include #include #include #include #include #include #include #include #include #include #include #include SDT_PROBE_DEFINE5_XLATE(sdt, , , m__init, "struct mbuf *", "mbufinfo_t *", "uint32_t", "uint32_t", "uint16_t", "uint16_t", "uint32_t", "uint32_t", "uint32_t", "uint32_t"); SDT_PROBE_DEFINE3_XLATE(sdt, , , m__gethdr, "uint32_t", "uint32_t", "uint16_t", "uint16_t", "struct mbuf *", "mbufinfo_t *"); SDT_PROBE_DEFINE3_XLATE(sdt, , , m__get, "uint32_t", "uint32_t", "uint16_t", "uint16_t", "struct mbuf *", "mbufinfo_t *"); SDT_PROBE_DEFINE4_XLATE(sdt, , , m__getcl, "uint32_t", "uint32_t", "uint16_t", "uint16_t", "uint32_t", "uint32_t", "struct mbuf *", "mbufinfo_t *"); SDT_PROBE_DEFINE3_XLATE(sdt, , , m__clget, "struct mbuf *", "mbufinfo_t *", "uint32_t", "uint32_t", "uint32_t", "uint32_t"); SDT_PROBE_DEFINE4_XLATE(sdt, , , m__cljget, "struct mbuf *", "mbufinfo_t *", "uint32_t", "uint32_t", "uint32_t", "uint32_t", "void*", "void*"); SDT_PROBE_DEFINE(sdt, , , m__cljset); SDT_PROBE_DEFINE1_XLATE(sdt, , , m__free, "struct mbuf *", "mbufinfo_t *"); SDT_PROBE_DEFINE1_XLATE(sdt, , , m__freem, "struct mbuf *", "mbufinfo_t *"); #include int max_linkhdr; int max_protohdr; int max_hdr; int max_datalen; #ifdef MBUF_STRESS_TEST int m_defragpackets; int m_defragbytes; int m_defraguseless; int m_defragfailure; int m_defragrandomfailures; #endif /* * sysctl(8) exported objects */ SYSCTL_INT(_kern_ipc, KIPC_MAX_LINKHDR, max_linkhdr, CTLFLAG_RD, &max_linkhdr, 0, "Size of largest link layer header"); SYSCTL_INT(_kern_ipc, KIPC_MAX_PROTOHDR, max_protohdr, CTLFLAG_RD, &max_protohdr, 0, "Size of largest protocol layer header"); SYSCTL_INT(_kern_ipc, KIPC_MAX_HDR, max_hdr, CTLFLAG_RD, &max_hdr, 0, "Size of largest link plus protocol header"); SYSCTL_INT(_kern_ipc, KIPC_MAX_DATALEN, max_datalen, CTLFLAG_RD, &max_datalen, 0, "Minimum space left in mbuf after max_hdr"); #ifdef MBUF_STRESS_TEST SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragpackets, CTLFLAG_RD, &m_defragpackets, 0, ""); SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragbytes, CTLFLAG_RD, &m_defragbytes, 0, ""); SYSCTL_INT(_kern_ipc, OID_AUTO, m_defraguseless, CTLFLAG_RD, &m_defraguseless, 0, ""); SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragfailure, CTLFLAG_RD, &m_defragfailure, 0, ""); SYSCTL_INT(_kern_ipc, OID_AUTO, m_defragrandomfailures, CTLFLAG_RW, &m_defragrandomfailures, 0, ""); #endif /* * Ensure the correct size of various mbuf parameters. It could be off due * to compiler-induced padding and alignment artifacts. */ CTASSERT(MSIZE - offsetof(struct mbuf, m_dat) == MLEN); CTASSERT(MSIZE - offsetof(struct mbuf, m_pktdat) == MHLEN); /* * mbuf data storage should be 64-bit aligned regardless of architectural * pointer size; check this is the case with and without a packet header. */ CTASSERT(offsetof(struct mbuf, m_dat) % 8 == 0); CTASSERT(offsetof(struct mbuf, m_pktdat) % 8 == 0); /* * While the specific values here don't matter too much (i.e., +/- a few * words), we do want to ensure that changes to these values are carefully * reasoned about and properly documented. This is especially the case as * network-protocol and device-driver modules encode these layouts, and must * be recompiled if the structures change. Check these values at compile time * against the ones documented in comments in mbuf.h. * * NB: Possibly they should be documented there via #define's and not just * comments. */ #if defined(__LP64__) CTASSERT(offsetof(struct mbuf, m_dat) == 32); CTASSERT(sizeof(struct pkthdr) == 56); CTASSERT(sizeof(struct m_ext) == 48); #else CTASSERT(offsetof(struct mbuf, m_dat) == 24); CTASSERT(sizeof(struct pkthdr) == 48); CTASSERT(sizeof(struct m_ext) == 28); #endif /* * Assert that the queue(3) macros produce code of the same size as an old * plain pointer does. */ #ifdef INVARIANTS static struct mbuf m_assertbuf; CTASSERT(sizeof(m_assertbuf.m_slist) == sizeof(m_assertbuf.m_next)); CTASSERT(sizeof(m_assertbuf.m_stailq) == sizeof(m_assertbuf.m_next)); CTASSERT(sizeof(m_assertbuf.m_slistpkt) == sizeof(m_assertbuf.m_nextpkt)); CTASSERT(sizeof(m_assertbuf.m_stailqpkt) == sizeof(m_assertbuf.m_nextpkt)); #endif /* * Attach the cluster from *m to *n, set up m_ext in *n * and bump the refcount of the cluster. */ void mb_dupcl(struct mbuf *n, struct mbuf *m) { volatile u_int *refcnt; KASSERT(m->m_flags & M_EXT, ("%s: M_EXT not set on %p", __func__, m)); KASSERT(!(n->m_flags & M_EXT), ("%s: M_EXT set on %p", __func__, n)); n->m_ext = m->m_ext; n->m_flags |= M_EXT; n->m_flags |= m->m_flags & M_RDONLY; /* See if this is the mbuf that holds the embedded refcount. */ if (m->m_ext.ext_flags & EXT_FLAG_EMBREF) { refcnt = n->m_ext.ext_cnt = &m->m_ext.ext_count; n->m_ext.ext_flags &= ~EXT_FLAG_EMBREF; } else { KASSERT(m->m_ext.ext_cnt != NULL, ("%s: no refcounting pointer on %p", __func__, m)); refcnt = m->m_ext.ext_cnt; } if (*refcnt == 1) *refcnt += 1; else atomic_add_int(refcnt, 1); } void m_demote_pkthdr(struct mbuf *m) { M_ASSERTPKTHDR(m); m_tag_delete_chain(m, NULL); m->m_flags &= ~M_PKTHDR; bzero(&m->m_pkthdr, sizeof(struct pkthdr)); } /* * Clean up mbuf (chain) from any tags and packet headers. * If "all" is set then the first mbuf in the chain will be * cleaned too. */ void m_demote(struct mbuf *m0, int all, int flags) { struct mbuf *m; for (m = all ? m0 : m0->m_next; m != NULL; m = m->m_next) { KASSERT(m->m_nextpkt == NULL, ("%s: m_nextpkt in m %p, m0 %p", __func__, m, m0)); if (m->m_flags & M_PKTHDR) m_demote_pkthdr(m); m->m_flags = m->m_flags & (M_EXT | M_RDONLY | M_NOFREE | flags); } } /* * Sanity checks on mbuf (chain) for use in KASSERT() and general * debugging. * Returns 0 or panics when bad and 1 on all tests passed. * Sanitize, 0 to run M_SANITY_ACTION, 1 to garble things so they * blow up later. */ int m_sanity(struct mbuf *m0, int sanitize) { struct mbuf *m; caddr_t a, b; int pktlen = 0; #ifdef INVARIANTS #define M_SANITY_ACTION(s) panic("mbuf %p: " s, m) #else #define M_SANITY_ACTION(s) printf("mbuf %p: " s, m) #endif for (m = m0; m != NULL; m = m->m_next) { /* * Basic pointer checks. If any of these fails then some * unrelated kernel memory before or after us is trashed. * No way to recover from that. */ a = M_START(m); b = a + M_SIZE(m); if ((caddr_t)m->m_data < a) M_SANITY_ACTION("m_data outside mbuf data range left"); if ((caddr_t)m->m_data > b) M_SANITY_ACTION("m_data outside mbuf data range right"); if ((caddr_t)m->m_data + m->m_len > b) M_SANITY_ACTION("m_data + m_len exeeds mbuf space"); /* m->m_nextpkt may only be set on first mbuf in chain. */ if (m != m0 && m->m_nextpkt != NULL) { if (sanitize) { m_freem(m->m_nextpkt); m->m_nextpkt = (struct mbuf *)0xDEADC0DE; } else M_SANITY_ACTION("m->m_nextpkt on in-chain mbuf"); } /* packet length (not mbuf length!) calculation */ if (m0->m_flags & M_PKTHDR) pktlen += m->m_len; /* m_tags may only be attached to first mbuf in chain. */ if (m != m0 && m->m_flags & M_PKTHDR && !SLIST_EMPTY(&m->m_pkthdr.tags)) { if (sanitize) { m_tag_delete_chain(m, NULL); /* put in 0xDEADC0DE perhaps? */ } else M_SANITY_ACTION("m_tags on in-chain mbuf"); } /* M_PKTHDR may only be set on first mbuf in chain */ if (m != m0 && m->m_flags & M_PKTHDR) { if (sanitize) { bzero(&m->m_pkthdr, sizeof(m->m_pkthdr)); m->m_flags &= ~M_PKTHDR; /* put in 0xDEADCODE and leave hdr flag in */ } else M_SANITY_ACTION("M_PKTHDR on in-chain mbuf"); } } m = m0; if (pktlen && pktlen != m->m_pkthdr.len) { if (sanitize) m->m_pkthdr.len = 0; else M_SANITY_ACTION("m_pkthdr.len != mbuf chain length"); } return 1; #undef M_SANITY_ACTION } /* * Non-inlined part of m_init(). */ int m_pkthdr_init(struct mbuf *m, int how) { #ifdef MAC int error; #endif m->m_data = m->m_pktdat; bzero(&m->m_pkthdr, sizeof(m->m_pkthdr)); #ifdef MAC /* If the label init fails, fail the alloc */ error = mac_mbuf_init(m, how); if (error) return (error); #endif return (0); } /* * "Move" mbuf pkthdr from "from" to "to". * "from" must have M_PKTHDR set, and "to" must be empty. */ void m_move_pkthdr(struct mbuf *to, struct mbuf *from) { #if 0 /* see below for why these are not enabled */ M_ASSERTPKTHDR(to); /* Note: with MAC, this may not be a good assertion. */ KASSERT(SLIST_EMPTY(&to->m_pkthdr.tags), ("m_move_pkthdr: to has tags")); #endif #ifdef MAC /* * XXXMAC: It could be this should also occur for non-MAC? */ if (to->m_flags & M_PKTHDR) m_tag_delete_chain(to, NULL); #endif to->m_flags = (from->m_flags & M_COPYFLAGS) | (to->m_flags & M_EXT); if ((to->m_flags & M_EXT) == 0) to->m_data = to->m_pktdat; to->m_pkthdr = from->m_pkthdr; /* especially tags */ SLIST_INIT(&from->m_pkthdr.tags); /* purge tags from src */ from->m_flags &= ~M_PKTHDR; } /* * Duplicate "from"'s mbuf pkthdr in "to". * "from" must have M_PKTHDR set, and "to" must be empty. * In particular, this does a deep copy of the packet tags. */ int m_dup_pkthdr(struct mbuf *to, const struct mbuf *from, int how) { #if 0 /* * The mbuf allocator only initializes the pkthdr * when the mbuf is allocated with m_gethdr(). Many users * (e.g. m_copy*, m_prepend) use m_get() and then * smash the pkthdr as needed causing these * assertions to trip. For now just disable them. */ M_ASSERTPKTHDR(to); /* Note: with MAC, this may not be a good assertion. */ KASSERT(SLIST_EMPTY(&to->m_pkthdr.tags), ("m_dup_pkthdr: to has tags")); #endif MBUF_CHECKSLEEP(how); #ifdef MAC if (to->m_flags & M_PKTHDR) m_tag_delete_chain(to, NULL); #endif to->m_flags = (from->m_flags & M_COPYFLAGS) | (to->m_flags & M_EXT); if ((to->m_flags & M_EXT) == 0) to->m_data = to->m_pktdat; to->m_pkthdr = from->m_pkthdr; SLIST_INIT(&to->m_pkthdr.tags); return (m_tag_copy_chain(to, from, how)); } /* * Lesser-used path for M_PREPEND: * allocate new mbuf to prepend to chain, * copy junk along. */ struct mbuf * m_prepend(struct mbuf *m, int len, int how) { struct mbuf *mn; if (m->m_flags & M_PKTHDR) mn = m_gethdr(how, m->m_type); else mn = m_get(how, m->m_type); if (mn == NULL) { m_freem(m); return (NULL); } if (m->m_flags & M_PKTHDR) m_move_pkthdr(mn, m); mn->m_next = m; m = mn; if (len < M_SIZE(m)) M_ALIGN(m, len); m->m_len = len; return (m); } /* * Make a copy of an mbuf chain starting "off0" bytes from the beginning, * continuing for "len" bytes. If len is M_COPYALL, copy to end of mbuf. * The wait parameter is a choice of M_WAITOK/M_NOWAIT from caller. * Note that the copy is read-only, because clusters are not copied, * only their reference counts are incremented. */ struct mbuf * m_copym(struct mbuf *m, int off0, int len, int wait) { struct mbuf *n, **np; int off = off0; struct mbuf *top; int copyhdr = 0; KASSERT(off >= 0, ("m_copym, negative off %d", off)); KASSERT(len >= 0, ("m_copym, negative len %d", len)); MBUF_CHECKSLEEP(wait); if (off == 0 && m->m_flags & M_PKTHDR) copyhdr = 1; while (off > 0) { KASSERT(m != NULL, ("m_copym, offset > size of mbuf chain")); if (off < m->m_len) break; off -= m->m_len; m = m->m_next; } np = ⊤ top = 0; while (len > 0) { if (m == NULL) { KASSERT(len == M_COPYALL, ("m_copym, length > size of mbuf chain")); break; } if (copyhdr) n = m_gethdr(wait, m->m_type); else n = m_get(wait, m->m_type); *np = n; if (n == NULL) goto nospace; if (copyhdr) { if (!m_dup_pkthdr(n, m, wait)) goto nospace; if (len == M_COPYALL) n->m_pkthdr.len -= off0; else n->m_pkthdr.len = len; copyhdr = 0; } n->m_len = min(len, m->m_len - off); if (m->m_flags & M_EXT) { n->m_data = m->m_data + off; mb_dupcl(n, m); } else bcopy(mtod(m, caddr_t)+off, mtod(n, caddr_t), (u_int)n->m_len); if (len != M_COPYALL) len -= n->m_len; off = 0; m = m->m_next; np = &n->m_next; } return (top); nospace: m_freem(top); return (NULL); } /* * Copy an entire packet, including header (which must be present). * An optimization of the common case `m_copym(m, 0, M_COPYALL, how)'. * Note that the copy is read-only, because clusters are not copied, * only their reference counts are incremented. * Preserve alignment of the first mbuf so if the creator has left * some room at the beginning (e.g. for inserting protocol headers) * the copies still have the room available. */ struct mbuf * m_copypacket(struct mbuf *m, int how) { struct mbuf *top, *n, *o; MBUF_CHECKSLEEP(how); n = m_get(how, m->m_type); top = n; if (n == NULL) goto nospace; if (!m_dup_pkthdr(n, m, how)) goto nospace; n->m_len = m->m_len; if (m->m_flags & M_EXT) { n->m_data = m->m_data; mb_dupcl(n, m); } else { n->m_data = n->m_pktdat + (m->m_data - m->m_pktdat ); bcopy(mtod(m, char *), mtod(n, char *), n->m_len); } m = m->m_next; while (m) { o = m_get(how, m->m_type); if (o == NULL) goto nospace; n->m_next = o; n = n->m_next; n->m_len = m->m_len; if (m->m_flags & M_EXT) { n->m_data = m->m_data; mb_dupcl(n, m); } else { bcopy(mtod(m, char *), mtod(n, char *), n->m_len); } m = m->m_next; } return top; nospace: m_freem(top); return (NULL); } /* * Copy data from an mbuf chain starting "off" bytes from the beginning, * continuing for "len" bytes, into the indicated buffer. */ void m_copydata(const struct mbuf *m, int off, int len, caddr_t cp) { u_int count; KASSERT(off >= 0, ("m_copydata, negative off %d", off)); KASSERT(len >= 0, ("m_copydata, negative len %d", len)); while (off > 0) { KASSERT(m != NULL, ("m_copydata, offset > size of mbuf chain")); if (off < m->m_len) break; off -= m->m_len; m = m->m_next; } while (len > 0) { KASSERT(m != NULL, ("m_copydata, length > size of mbuf chain")); count = min(m->m_len - off, len); bcopy(mtod(m, caddr_t) + off, cp, count); len -= count; cp += count; off = 0; m = m->m_next; } } /* * Copy a packet header mbuf chain into a completely new chain, including * copying any mbuf clusters. Use this instead of m_copypacket() when * you need a writable copy of an mbuf chain. */ struct mbuf * m_dup(const struct mbuf *m, int how) { struct mbuf **p, *top = NULL; int remain, moff, nsize; MBUF_CHECKSLEEP(how); /* Sanity check */ if (m == NULL) return (NULL); M_ASSERTPKTHDR(m); /* While there's more data, get a new mbuf, tack it on, and fill it */ remain = m->m_pkthdr.len; moff = 0; p = ⊤ while (remain > 0 || top == NULL) { /* allow m->m_pkthdr.len == 0 */ struct mbuf *n; /* Get the next new mbuf */ if (remain >= MINCLSIZE) { n = m_getcl(how, m->m_type, 0); nsize = MCLBYTES; } else { n = m_get(how, m->m_type); nsize = MLEN; } if (n == NULL) goto nospace; if (top == NULL) { /* First one, must be PKTHDR */ if (!m_dup_pkthdr(n, m, how)) { m_free(n); goto nospace; } if ((n->m_flags & M_EXT) == 0) nsize = MHLEN; n->m_flags &= ~M_RDONLY; } n->m_len = 0; /* Link it into the new chain */ *p = n; p = &n->m_next; /* Copy data from original mbuf(s) into new mbuf */ while (n->m_len < nsize && m != NULL) { int chunk = min(nsize - n->m_len, m->m_len - moff); bcopy(m->m_data + moff, n->m_data + n->m_len, chunk); moff += chunk; n->m_len += chunk; remain -= chunk; if (moff == m->m_len) { m = m->m_next; moff = 0; } } /* Check correct total mbuf length */ KASSERT((remain > 0 && m != NULL) || (remain == 0 && m == NULL), ("%s: bogus m_pkthdr.len", __func__)); } return (top); nospace: m_freem(top); return (NULL); } /* * Concatenate mbuf chain n to m. * Both chains must be of the same type (e.g. MT_DATA). * Any m_pkthdr is not updated. */ void m_cat(struct mbuf *m, struct mbuf *n) { while (m->m_next) m = m->m_next; while (n) { if (!M_WRITABLE(m) || M_TRAILINGSPACE(m) < n->m_len) { /* just join the two chains */ m->m_next = n; return; } /* splat the data from one into the other */ bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len, (u_int)n->m_len); m->m_len += n->m_len; n = m_free(n); } } /* * Concatenate two pkthdr mbuf chains. */ void m_catpkt(struct mbuf *m, struct mbuf *n) { M_ASSERTPKTHDR(m); M_ASSERTPKTHDR(n); m->m_pkthdr.len += n->m_pkthdr.len; m_demote(n, 1, 0); m_cat(m, n); } void m_adj(struct mbuf *mp, int req_len) { int len = req_len; struct mbuf *m; int count; if ((m = mp) == NULL) return; if (len >= 0) { /* * Trim from head. */ while (m != NULL && len > 0) { if (m->m_len <= len) { len -= m->m_len; m->m_len = 0; m = m->m_next; } else { m->m_len -= len; m->m_data += len; len = 0; } } if (mp->m_flags & M_PKTHDR) mp->m_pkthdr.len -= (req_len - len); } else { /* * Trim from tail. Scan the mbuf chain, * calculating its length and finding the last mbuf. * If the adjustment only affects this mbuf, then just * adjust and return. Otherwise, rescan and truncate * after the remaining size. */ len = -len; count = 0; for (;;) { count += m->m_len; if (m->m_next == (struct mbuf *)0) break; m = m->m_next; } if (m->m_len >= len) { m->m_len -= len; if (mp->m_flags & M_PKTHDR) mp->m_pkthdr.len -= len; return; } count -= len; if (count < 0) count = 0; /* * Correct length for chain is "count". * Find the mbuf with last data, adjust its length, * and toss data from remaining mbufs on chain. */ m = mp; if (m->m_flags & M_PKTHDR) m->m_pkthdr.len = count; for (; m; m = m->m_next) { if (m->m_len >= count) { m->m_len = count; if (m->m_next != NULL) { m_freem(m->m_next); m->m_next = NULL; } break; } count -= m->m_len; } } } /* * Rearange an mbuf chain so that len bytes are contiguous * and in the data area of an mbuf (so that mtod will work * for a structure of size len). Returns the resulting * mbuf chain on success, frees it and returns null on failure. * If there is room, it will add up to max_protohdr-len extra bytes to the * contiguous region in an attempt to avoid being called next time. */ struct mbuf * m_pullup(struct mbuf *n, int len) { struct mbuf *m; int count; int space; /* * If first mbuf has no cluster, and has room for len bytes * without shifting current data, pullup into it, * otherwise allocate a new mbuf to prepend to the chain. */ if ((n->m_flags & M_EXT) == 0 && n->m_data + len < &n->m_dat[MLEN] && n->m_next) { if (n->m_len >= len) return (n); m = n; n = n->m_next; len -= m->m_len; } else { if (len > MHLEN) goto bad; m = m_get(M_NOWAIT, n->m_type); if (m == NULL) goto bad; if (n->m_flags & M_PKTHDR) m_move_pkthdr(m, n); } space = &m->m_dat[MLEN] - (m->m_data + m->m_len); do { count = min(min(max(len, max_protohdr), space), n->m_len); bcopy(mtod(n, caddr_t), mtod(m, caddr_t) + m->m_len, (u_int)count); len -= count; m->m_len += count; n->m_len -= count; space -= count; if (n->m_len) n->m_data += count; else n = m_free(n); } while (len > 0 && n); if (len > 0) { (void) m_free(m); goto bad; } m->m_next = n; return (m); bad: m_freem(n); return (NULL); } /* * Like m_pullup(), except a new mbuf is always allocated, and we allow * the amount of empty space before the data in the new mbuf to be specified * (in the event that the caller expects to prepend later). */ struct mbuf * m_copyup(struct mbuf *n, int len, int dstoff) { struct mbuf *m; int count, space; if (len > (MHLEN - dstoff)) goto bad; m = m_get(M_NOWAIT, n->m_type); if (m == NULL) goto bad; if (n->m_flags & M_PKTHDR) m_move_pkthdr(m, n); m->m_data += dstoff; space = &m->m_dat[MLEN] - (m->m_data + m->m_len); do { count = min(min(max(len, max_protohdr), space), n->m_len); memcpy(mtod(m, caddr_t) + m->m_len, mtod(n, caddr_t), (unsigned)count); len -= count; m->m_len += count; n->m_len -= count; space -= count; if (n->m_len) n->m_data += count; else n = m_free(n); } while (len > 0 && n); if (len > 0) { (void) m_free(m); goto bad; } m->m_next = n; return (m); bad: m_freem(n); return (NULL); } /* * Partition an mbuf chain in two pieces, returning the tail -- * all but the first len0 bytes. In case of failure, it returns NULL and * attempts to restore the chain to its original state. * * Note that the resulting mbufs might be read-only, because the new * mbuf can end up sharing an mbuf cluster with the original mbuf if * the "breaking point" happens to lie within a cluster mbuf. Use the * M_WRITABLE() macro to check for this case. */ struct mbuf * m_split(struct mbuf *m0, int len0, int wait) { struct mbuf *m, *n; u_int len = len0, remain; MBUF_CHECKSLEEP(wait); for (m = m0; m && len > m->m_len; m = m->m_next) len -= m->m_len; if (m == NULL) return (NULL); remain = m->m_len - len; if (m0->m_flags & M_PKTHDR && remain == 0) { n = m_gethdr(wait, m0->m_type); if (n == NULL) return (NULL); n->m_next = m->m_next; m->m_next = NULL; n->m_pkthdr.rcvif = m0->m_pkthdr.rcvif; n->m_pkthdr.len = m0->m_pkthdr.len - len0; m0->m_pkthdr.len = len0; return (n); } else if (m0->m_flags & M_PKTHDR) { n = m_gethdr(wait, m0->m_type); if (n == NULL) return (NULL); n->m_pkthdr.rcvif = m0->m_pkthdr.rcvif; n->m_pkthdr.len = m0->m_pkthdr.len - len0; m0->m_pkthdr.len = len0; if (m->m_flags & M_EXT) goto extpacket; if (remain > MHLEN) { /* m can't be the lead packet */ M_ALIGN(n, 0); n->m_next = m_split(m, len, wait); if (n->m_next == NULL) { (void) m_free(n); return (NULL); } else { n->m_len = 0; return (n); } } else M_ALIGN(n, remain); } else if (remain == 0) { n = m->m_next; m->m_next = NULL; return (n); } else { n = m_get(wait, m->m_type); if (n == NULL) return (NULL); M_ALIGN(n, remain); } extpacket: if (m->m_flags & M_EXT) { n->m_data = m->m_data + len; mb_dupcl(n, m); } else { bcopy(mtod(m, caddr_t) + len, mtod(n, caddr_t), remain); } n->m_len = remain; m->m_len = len; n->m_next = m->m_next; m->m_next = NULL; return (n); } /* * Routine to copy from device local memory into mbufs. * Note that `off' argument is offset into first mbuf of target chain from * which to begin copying the data to. */ struct mbuf * m_devget(char *buf, int totlen, int off, struct ifnet *ifp, void (*copy)(char *from, caddr_t to, u_int len)) { struct mbuf *m; struct mbuf *top = NULL, **mp = ⊤ int len; if (off < 0 || off > MHLEN) return (NULL); while (totlen > 0) { if (top == NULL) { /* First one, must be PKTHDR */ if (totlen + off >= MINCLSIZE) { m = m_getcl(M_NOWAIT, MT_DATA, M_PKTHDR); len = MCLBYTES; } else { m = m_gethdr(M_NOWAIT, MT_DATA); len = MHLEN; /* Place initial small packet/header at end of mbuf */ if (m && totlen + off + max_linkhdr <= MLEN) { m->m_data += max_linkhdr; len -= max_linkhdr; } } if (m == NULL) return NULL; m->m_pkthdr.rcvif = ifp; m->m_pkthdr.len = totlen; } else { if (totlen + off >= MINCLSIZE) { m = m_getcl(M_NOWAIT, MT_DATA, 0); len = MCLBYTES; } else { m = m_get(M_NOWAIT, MT_DATA); len = MLEN; } if (m == NULL) { m_freem(top); return NULL; } } if (off) { m->m_data += off; len -= off; off = 0; } m->m_len = len = min(totlen, len); if (copy) copy(buf, mtod(m, caddr_t), (u_int)len); else bcopy(buf, mtod(m, caddr_t), (u_int)len); buf += len; *mp = m; mp = &m->m_next; totlen -= len; } return (top); } /* * Copy data from a buffer back into the indicated mbuf chain, * starting "off" bytes from the beginning, extending the mbuf * chain if necessary. */ void m_copyback(struct mbuf *m0, int off, int len, c_caddr_t cp) { int mlen; struct mbuf *m = m0, *n; int totlen = 0; if (m0 == NULL) return; while (off > (mlen = m->m_len)) { off -= mlen; totlen += mlen; if (m->m_next == NULL) { n = m_get(M_NOWAIT, m->m_type); if (n == NULL) goto out; bzero(mtod(n, caddr_t), MLEN); n->m_len = min(MLEN, len + off); m->m_next = n; } m = m->m_next; } while (len > 0) { if (m->m_next == NULL && (len > m->m_len - off)) { m->m_len += min(len - (m->m_len - off), M_TRAILINGSPACE(m)); } mlen = min (m->m_len - off, len); bcopy(cp, off + mtod(m, caddr_t), (u_int)mlen); cp += mlen; len -= mlen; mlen += off; off = 0; totlen += mlen; if (len == 0) break; if (m->m_next == NULL) { n = m_get(M_NOWAIT, m->m_type); if (n == NULL) break; n->m_len = min(MLEN, len); m->m_next = n; } m = m->m_next; } out: if (((m = m0)->m_flags & M_PKTHDR) && (m->m_pkthdr.len < totlen)) m->m_pkthdr.len = totlen; } /* * Append the specified data to the indicated mbuf chain, * Extend the mbuf chain if the new data does not fit in * existing space. * * Return 1 if able to complete the job; otherwise 0. */ int m_append(struct mbuf *m0, int len, c_caddr_t cp) { struct mbuf *m, *n; int remainder, space; for (m = m0; m->m_next != NULL; m = m->m_next) ; remainder = len; space = M_TRAILINGSPACE(m); if (space > 0) { /* * Copy into available space. */ if (space > remainder) space = remainder; bcopy(cp, mtod(m, caddr_t) + m->m_len, space); m->m_len += space; cp += space, remainder -= space; } while (remainder > 0) { /* * Allocate a new mbuf; could check space * and allocate a cluster instead. */ n = m_get(M_NOWAIT, m->m_type); if (n == NULL) break; n->m_len = min(MLEN, remainder); bcopy(cp, mtod(n, caddr_t), n->m_len); cp += n->m_len, remainder -= n->m_len; m->m_next = n; m = n; } if (m0->m_flags & M_PKTHDR) m0->m_pkthdr.len += len - remainder; return (remainder == 0); } /* * Apply function f to the data in an mbuf chain starting "off" bytes from * the beginning, continuing for "len" bytes. */ int m_apply(struct mbuf *m, int off, int len, int (*f)(void *, void *, u_int), void *arg) { u_int count; int rval; KASSERT(off >= 0, ("m_apply, negative off %d", off)); KASSERT(len >= 0, ("m_apply, negative len %d", len)); while (off > 0) { KASSERT(m != NULL, ("m_apply, offset > size of mbuf chain")); if (off < m->m_len) break; off -= m->m_len; m = m->m_next; } while (len > 0) { KASSERT(m != NULL, ("m_apply, offset > size of mbuf chain")); count = min(m->m_len - off, len); rval = (*f)(arg, mtod(m, caddr_t) + off, count); if (rval) return (rval); len -= count; off = 0; m = m->m_next; } return (0); } /* * Return a pointer to mbuf/offset of location in mbuf chain. */ struct mbuf * m_getptr(struct mbuf *m, int loc, int *off) { while (loc >= 0) { /* Normal end of search. */ if (m->m_len > loc) { *off = loc; return (m); } else { loc -= m->m_len; if (m->m_next == NULL) { if (loc == 0) { /* Point at the end of valid data. */ *off = m->m_len; return (m); } return (NULL); } m = m->m_next; } } return (NULL); } void m_print(const struct mbuf *m, int maxlen) { int len; int pdata; const struct mbuf *m2; if (m == NULL) { printf("mbuf: %p\n", m); return; } if (m->m_flags & M_PKTHDR) len = m->m_pkthdr.len; else len = -1; m2 = m; while (m2 != NULL && (len == -1 || len)) { pdata = m2->m_len; if (maxlen != -1 && pdata > maxlen) pdata = maxlen; printf("mbuf: %p len: %d, next: %p, %b%s", m2, m2->m_len, m2->m_next, m2->m_flags, "\20\20freelist\17skipfw" "\11proto5\10proto4\7proto3\6proto2\5proto1\4rdonly" "\3eor\2pkthdr\1ext", pdata ? "" : "\n"); if (pdata) printf(", %*D\n", pdata, (u_char *)m2->m_data, "-"); if (len != -1) len -= m2->m_len; m2 = m2->m_next; } if (len > 0) printf("%d bytes unaccounted for.\n", len); return; } u_int m_fixhdr(struct mbuf *m0) { u_int len; len = m_length(m0, NULL); m0->m_pkthdr.len = len; return (len); } u_int m_length(struct mbuf *m0, struct mbuf **last) { struct mbuf *m; u_int len; len = 0; for (m = m0; m != NULL; m = m->m_next) { len += m->m_len; if (m->m_next == NULL) break; } if (last != NULL) *last = m; return (len); } /* * Defragment a mbuf chain, returning the shortest possible * chain of mbufs and clusters. If allocation fails and * this cannot be completed, NULL will be returned, but * the passed in chain will be unchanged. Upon success, * the original chain will be freed, and the new chain * will be returned. * * If a non-packet header is passed in, the original * mbuf (chain?) will be returned unharmed. */ struct mbuf * m_defrag(struct mbuf *m0, int how) { struct mbuf *m_new = NULL, *m_final = NULL; int progress = 0, length; MBUF_CHECKSLEEP(how); if (!(m0->m_flags & M_PKTHDR)) return (m0); m_fixhdr(m0); /* Needed sanity check */ #ifdef MBUF_STRESS_TEST if (m_defragrandomfailures) { int temp = arc4random() & 0xff; if (temp == 0xba) goto nospace; } #endif if (m0->m_pkthdr.len > MHLEN) m_final = m_getcl(how, MT_DATA, M_PKTHDR); else m_final = m_gethdr(how, MT_DATA); if (m_final == NULL) goto nospace; if (m_dup_pkthdr(m_final, m0, how) == 0) goto nospace; m_new = m_final; while (progress < m0->m_pkthdr.len) { length = m0->m_pkthdr.len - progress; if (length > MCLBYTES) length = MCLBYTES; if (m_new == NULL) { if (length > MLEN) m_new = m_getcl(how, MT_DATA, 0); else m_new = m_get(how, MT_DATA); if (m_new == NULL) goto nospace; } m_copydata(m0, progress, length, mtod(m_new, caddr_t)); progress += length; m_new->m_len = length; if (m_new != m_final) m_cat(m_final, m_new); m_new = NULL; } #ifdef MBUF_STRESS_TEST if (m0->m_next == NULL) m_defraguseless++; #endif m_freem(m0); m0 = m_final; #ifdef MBUF_STRESS_TEST m_defragpackets++; m_defragbytes += m0->m_pkthdr.len; #endif return (m0); nospace: #ifdef MBUF_STRESS_TEST m_defragfailure++; #endif if (m_final) m_freem(m_final); return (NULL); } /* * Defragment an mbuf chain, returning at most maxfrags separate * mbufs+clusters. If this is not possible NULL is returned and * the original mbuf chain is left in it's present (potentially * modified) state. We use two techniques: collapsing consecutive * mbufs and replacing consecutive mbufs by a cluster. * * NB: this should really be named m_defrag but that name is taken */ struct mbuf * m_collapse(struct mbuf *m0, int how, int maxfrags) { struct mbuf *m, *n, *n2, **prev; u_int curfrags; /* * Calculate the current number of frags. */ curfrags = 0; for (m = m0; m != NULL; m = m->m_next) curfrags++; /* * First, try to collapse mbufs. Note that we always collapse * towards the front so we don't need to deal with moving the * pkthdr. This may be suboptimal if the first mbuf has much * less data than the following. */ m = m0; again: for (;;) { n = m->m_next; if (n == NULL) break; if (M_WRITABLE(m) && n->m_len < M_TRAILINGSPACE(m)) { bcopy(mtod(n, void *), mtod(m, char *) + m->m_len, n->m_len); m->m_len += n->m_len; m->m_next = n->m_next; m_free(n); if (--curfrags <= maxfrags) return m0; } else m = n; } KASSERT(maxfrags > 1, ("maxfrags %u, but normal collapse failed", maxfrags)); /* * Collapse consecutive mbufs to a cluster. */ prev = &m0->m_next; /* NB: not the first mbuf */ while ((n = *prev) != NULL) { if ((n2 = n->m_next) != NULL && n->m_len + n2->m_len < MCLBYTES) { m = m_getcl(how, MT_DATA, 0); if (m == NULL) goto bad; bcopy(mtod(n, void *), mtod(m, void *), n->m_len); bcopy(mtod(n2, void *), mtod(m, char *) + n->m_len, n2->m_len); m->m_len = n->m_len + n2->m_len; m->m_next = n2->m_next; *prev = m; m_free(n); m_free(n2); if (--curfrags <= maxfrags) /* +1 cl -2 mbufs */ return m0; /* * Still not there, try the normal collapse * again before we allocate another cluster. */ goto again; } prev = &n->m_next; } /* * No place where we can collapse to a cluster; punt. * This can occur if, for example, you request 2 frags * but the packet requires that both be clusters (we * never reallocate the first mbuf to avoid moving the * packet header). */ bad: return NULL; } #ifdef MBUF_STRESS_TEST /* * Fragment an mbuf chain. There's no reason you'd ever want to do * this in normal usage, but it's great for stress testing various * mbuf consumers. * * If fragmentation is not possible, the original chain will be * returned. * * Possible length values: * 0 no fragmentation will occur * > 0 each fragment will be of the specified length * -1 each fragment will be the same random value in length * -2 each fragment's length will be entirely random * (Random values range from 1 to 256) */ struct mbuf * m_fragment(struct mbuf *m0, int how, int length) { struct mbuf *m_new = NULL, *m_final = NULL; int progress = 0; if (!(m0->m_flags & M_PKTHDR)) return (m0); if ((length == 0) || (length < -2)) return (m0); m_fixhdr(m0); /* Needed sanity check */ m_final = m_getcl(how, MT_DATA, M_PKTHDR); if (m_final == NULL) goto nospace; if (m_dup_pkthdr(m_final, m0, how) == 0) goto nospace; m_new = m_final; if (length == -1) length = 1 + (arc4random() & 255); while (progress < m0->m_pkthdr.len) { int fraglen; if (length > 0) fraglen = length; else fraglen = 1 + (arc4random() & 255); if (fraglen > m0->m_pkthdr.len - progress) fraglen = m0->m_pkthdr.len - progress; if (fraglen > MCLBYTES) fraglen = MCLBYTES; if (m_new == NULL) { m_new = m_getcl(how, MT_DATA, 0); if (m_new == NULL) goto nospace; } m_copydata(m0, progress, fraglen, mtod(m_new, caddr_t)); progress += fraglen; m_new->m_len = fraglen; if (m_new != m_final) m_cat(m_final, m_new); m_new = NULL; } m_freem(m0); m0 = m_final; return (m0); nospace: if (m_final) m_freem(m_final); /* Return the original chain on failure */ return (m0); } #endif /* * Copy the contents of uio into a properly sized mbuf chain. */ struct mbuf * m_uiotombuf(struct uio *uio, int how, int len, int align, int flags) { struct mbuf *m, *mb; int error, length; ssize_t total; int progress = 0; /* * len can be zero or an arbitrary large value bound by * the total data supplied by the uio. */ if (len > 0) total = min(uio->uio_resid, len); else total = uio->uio_resid; /* * The smallest unit returned by m_getm2() is a single mbuf * with pkthdr. We can't align past it. */ if (align >= MHLEN) return (NULL); /* * Give us the full allocation or nothing. * If len is zero return the smallest empty mbuf. */ m = m_getm2(NULL, max(total + align, 1), how, MT_DATA, flags); if (m == NULL) return (NULL); m->m_data += align; /* Fill all mbufs with uio data and update header information. */ for (mb = m; mb != NULL; mb = mb->m_next) { length = min(M_TRAILINGSPACE(mb), total - progress); error = uiomove(mtod(mb, void *), length, uio); if (error) { m_freem(m); return (NULL); } mb->m_len = length; progress += length; if (flags & M_PKTHDR) m->m_pkthdr.len += length; } KASSERT(progress == total, ("%s: progress != total", __func__)); return (m); } /* * Copy an mbuf chain into a uio limited by len if set. */ int m_mbuftouio(struct uio *uio, struct mbuf *m, int len) { int error, length, total; int progress = 0; if (len > 0) total = min(uio->uio_resid, len); else total = uio->uio_resid; /* Fill the uio with data from the mbufs. */ for (; m != NULL; m = m->m_next) { length = min(m->m_len, total - progress); error = uiomove(mtod(m, void *), length, uio); if (error) return (error); progress += length; } return (0); } /* * Create a writable copy of the mbuf chain. While doing this * we compact the chain with a goal of producing a chain with * at most two mbufs. The second mbuf in this chain is likely * to be a cluster. The primary purpose of this work is to create * a writable packet for encryption, compression, etc. The * secondary goal is to linearize the data so the data can be * passed to crypto hardware in the most efficient manner possible. */ struct mbuf * m_unshare(struct mbuf *m0, int how) { struct mbuf *m, *mprev; struct mbuf *n, *mfirst, *mlast; int len, off; mprev = NULL; for (m = m0; m != NULL; m = mprev->m_next) { /* * Regular mbufs are ignored unless there's a cluster * in front of it that we can use to coalesce. We do * the latter mainly so later clusters can be coalesced * also w/o having to handle them specially (i.e. convert * mbuf+cluster -> cluster). This optimization is heavily * influenced by the assumption that we're running over * Ethernet where MCLBYTES is large enough that the max * packet size will permit lots of coalescing into a * single cluster. This in turn permits efficient * crypto operations, especially when using hardware. */ if ((m->m_flags & M_EXT) == 0) { if (mprev && (mprev->m_flags & M_EXT) && m->m_len <= M_TRAILINGSPACE(mprev)) { /* XXX: this ignores mbuf types */ memcpy(mtod(mprev, caddr_t) + mprev->m_len, mtod(m, caddr_t), m->m_len); mprev->m_len += m->m_len; mprev->m_next = m->m_next; /* unlink from chain */ m_free(m); /* reclaim mbuf */ #if 0 newipsecstat.ips_mbcoalesced++; #endif } else { mprev = m; } continue; } /* * Writable mbufs are left alone (for now). */ if (M_WRITABLE(m)) { mprev = m; continue; } /* * Not writable, replace with a copy or coalesce with * the previous mbuf if possible (since we have to copy * it anyway, we try to reduce the number of mbufs and * clusters so that future work is easier). */ KASSERT(m->m_flags & M_EXT, ("m_flags 0x%x", m->m_flags)); /* NB: we only coalesce into a cluster or larger */ if (mprev != NULL && (mprev->m_flags & M_EXT) && m->m_len <= M_TRAILINGSPACE(mprev)) { /* XXX: this ignores mbuf types */ memcpy(mtod(mprev, caddr_t) + mprev->m_len, mtod(m, caddr_t), m->m_len); mprev->m_len += m->m_len; mprev->m_next = m->m_next; /* unlink from chain */ m_free(m); /* reclaim mbuf */ #if 0 newipsecstat.ips_clcoalesced++; #endif continue; } /* * Allocate new space to hold the copy and copy the data. * We deal with jumbo mbufs (i.e. m_len > MCLBYTES) by * splitting them into clusters. We could just malloc a * buffer and make it external but too many device drivers * don't know how to break up the non-contiguous memory when * doing DMA. */ - n = m_getcl(how, m->m_type, m->m_flags); + n = m_getcl(how, m->m_type, m->m_flags & M_COPYFLAGS); if (n == NULL) { m_freem(m0); return (NULL); } if (m->m_flags & M_PKTHDR) { KASSERT(mprev == NULL, ("%s: m0 %p, m %p has M_PKTHDR", __func__, m0, m)); m_move_pkthdr(n, m); } len = m->m_len; off = 0; mfirst = n; mlast = NULL; for (;;) { int cc = min(len, MCLBYTES); memcpy(mtod(n, caddr_t), mtod(m, caddr_t) + off, cc); n->m_len = cc; if (mlast != NULL) mlast->m_next = n; mlast = n; #if 0 newipsecstat.ips_clcopied++; #endif len -= cc; if (len <= 0) break; off += cc; - n = m_getcl(how, m->m_type, m->m_flags); + n = m_getcl(how, m->m_type, m->m_flags & M_COPYFLAGS); if (n == NULL) { m_freem(mfirst); m_freem(m0); return (NULL); } } n->m_next = m->m_next; if (mprev == NULL) m0 = mfirst; /* new head of chain */ else mprev->m_next = mfirst; /* replace old mbuf */ m_free(m); /* release old mbuf */ mprev = mfirst; } return (m0); } #ifdef MBUF_PROFILING #define MP_BUCKETS 32 /* don't just change this as things may overflow.*/ struct mbufprofile { uintmax_t wasted[MP_BUCKETS]; uintmax_t used[MP_BUCKETS]; uintmax_t segments[MP_BUCKETS]; } mbprof; #define MP_MAXDIGITS 21 /* strlen("16,000,000,000,000,000,000") == 21 */ #define MP_NUMLINES 6 #define MP_NUMSPERLINE 16 #define MP_EXTRABYTES 64 /* > strlen("used:\nwasted:\nsegments:\n") */ /* work out max space needed and add a bit of spare space too */ #define MP_MAXLINE ((MP_MAXDIGITS+1) * MP_NUMSPERLINE) #define MP_BUFSIZE ((MP_MAXLINE * MP_NUMLINES) + 1 + MP_EXTRABYTES) char mbprofbuf[MP_BUFSIZE]; void m_profile(struct mbuf *m) { int segments = 0; int used = 0; int wasted = 0; while (m) { segments++; used += m->m_len; if (m->m_flags & M_EXT) { wasted += MHLEN - sizeof(m->m_ext) + m->m_ext.ext_size - m->m_len; } else { if (m->m_flags & M_PKTHDR) wasted += MHLEN - m->m_len; else wasted += MLEN - m->m_len; } m = m->m_next; } /* be paranoid.. it helps */ if (segments > MP_BUCKETS - 1) segments = MP_BUCKETS - 1; if (used > 100000) used = 100000; if (wasted > 100000) wasted = 100000; /* store in the appropriate bucket */ /* don't bother locking. if it's slightly off, so what? */ mbprof.segments[segments]++; mbprof.used[fls(used)]++; mbprof.wasted[fls(wasted)]++; } static void mbprof_textify(void) { int offset; char *c; uint64_t *p; p = &mbprof.wasted[0]; c = mbprofbuf; offset = snprintf(c, MP_MAXLINE + 10, "wasted:\n" "%ju %ju %ju %ju %ju %ju %ju %ju " "%ju %ju %ju %ju %ju %ju %ju %ju\n", p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); #ifdef BIG_ARRAY p = &mbprof.wasted[16]; c += offset; offset = snprintf(c, MP_MAXLINE, "%ju %ju %ju %ju %ju %ju %ju %ju " "%ju %ju %ju %ju %ju %ju %ju %ju\n", p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); #endif p = &mbprof.used[0]; c += offset; offset = snprintf(c, MP_MAXLINE + 10, "used:\n" "%ju %ju %ju %ju %ju %ju %ju %ju " "%ju %ju %ju %ju %ju %ju %ju %ju\n", p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); #ifdef BIG_ARRAY p = &mbprof.used[16]; c += offset; offset = snprintf(c, MP_MAXLINE, "%ju %ju %ju %ju %ju %ju %ju %ju " "%ju %ju %ju %ju %ju %ju %ju %ju\n", p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); #endif p = &mbprof.segments[0]; c += offset; offset = snprintf(c, MP_MAXLINE + 10, "segments:\n" "%ju %ju %ju %ju %ju %ju %ju %ju " "%ju %ju %ju %ju %ju %ju %ju %ju\n", p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); #ifdef BIG_ARRAY p = &mbprof.segments[16]; c += offset; offset = snprintf(c, MP_MAXLINE, "%ju %ju %ju %ju %ju %ju %ju %ju " "%ju %ju %ju %ju %ju %ju %ju %jju", p[0], p[1], p[2], p[3], p[4], p[5], p[6], p[7], p[8], p[9], p[10], p[11], p[12], p[13], p[14], p[15]); #endif } static int mbprof_handler(SYSCTL_HANDLER_ARGS) { int error; mbprof_textify(); error = SYSCTL_OUT(req, mbprofbuf, strlen(mbprofbuf) + 1); return (error); } static int mbprof_clr_handler(SYSCTL_HANDLER_ARGS) { int clear, error; clear = 0; error = sysctl_handle_int(oidp, &clear, 0, req); if (error || !req->newptr) return (error); if (clear) { bzero(&mbprof, sizeof(mbprof)); } return (error); } SYSCTL_PROC(_kern_ipc, OID_AUTO, mbufprofile, CTLTYPE_STRING|CTLFLAG_RD, NULL, 0, mbprof_handler, "A", "mbuf profiling statistics"); SYSCTL_PROC(_kern_ipc, OID_AUTO, mbufprofileclr, CTLTYPE_INT|CTLFLAG_RW, NULL, 0, mbprof_clr_handler, "I", "clear mbuf profiling statistics"); #endif